Read AN INTRODUCTION TO THE HUMAN BODY text version

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BIS 240 HUMAN ANATOMY AND PHYSIOLGY I

LECTURE NOTES & LABORATORY OBJECTIVES

Judy Jiang, Ph.D. Science Department Triton College Revised Summer, 2010

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TABLE OF CONTENTS Unit 1 1. Introduction 2. Cells 3. Tissues 4. The Integumentary System Unit 2 5. Bone Tissue & Skeletal System 6. Joints 7. Nervous Tissue & Nervous System 8. Muscular Tissue Unit 3 9. The Cardiovascular System: The Heart 10. The Cardiovascular System: Blood Vessels 11. Back Region Unit 4 12. Upper Limb Region Unit 5 13. Lower Limb Region Unit 6 14. Head & Neck Regions Autonomic Nervous System Unit 7 15. Thorax, Respiratory System 16. Abdomen, Digestive System 17. Pelvis, Urinary & Reproductive Systems Appendix Oral Laboratory Identification Cadaver Care Grade Portfolio

PAGES 3 9 15 22 27 33 36 45 51 57 65 73 81 88 98

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AN INTRODUCTION TO THE HUMAN BODY

CHAPTER 1

ANATOMY DEFINED p.3 Anatomy: is the study of structure and the relationship among structures. Subdisciplines of Anatomy (Table 1.1) Gross or macroscopic: is the study of large body structures visible to the naked eye, such as heart, lungs, and kidneys. - Regional ­ all structures in one part of the body (such as the abdomen or leg) - Systemic ­ gross anatomy of the body studied by system - Surface ­ study of internal structures as they relate to the overlying skin Microscopic Anatomy: concerns structures too small to be seen with the naked eye. - Cytology ­ study of the cell - Histology ­ study of tissues Developmental biology: Structures that emerge from the time of the fertilized egg to the adult life. Embryology ­ study of developmental changes of the body before birth (the fertilized egg through the eighth week in uterus). Specialized Branches of Anatomy Pathological anatomy ­ study of structural changes caused by disease Radiographic anatomy ­ study of internal structures visualized by X ray Regional anatomy ­ Specific regions of the body such as the head or chest - Molecular biology ­ study of anatomical structures at a subcellular level - Physiology: deals with functions of body parts. LEVELS OF BODY ORGANIZATION 1. Chemical level: include atoms and molecules. 2. Cellular level: cells are the basic structural and functional units of an organism and are the smallest living units in the human body. 3. Tissue level: groups of cells and the materials surrounding them that work together to perform a particular function. 4. Organ level: organs are structures that are composed of two or more different types of tissues; they have specific functions, and recognizable shapes. 5. System level: consists of related organs that have a common function. 6. Organismal level: an organism is any living individual. The 11 Systems of the Human Body (Table 1.2; see the Exercise 1) Integumentary system Forms the external body covering Composed of the skin, sweat glands, oil glands, hair, and nails Protects deep tissues from injury and synthesizes vitamin D Skeletal system Composed of bone, cartilage, and ligaments Protects and supports body organs Provides the framework for muscles Site of blood cell formation Stores minerals p.4

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Muscular system Composed of muscles and tendons Allows manipulation of the environment, locomotion, and facial expression Maintains posture Produces heat Nervous system Composed of the brain, spinal column, and nerves Is the fast-acting control system of the body Responds to stimuli by activating muscles and glands Cardiovascular system Composed of the heart and blood vessels The heart pumps blood The blood vessels transport blood throughout the body Lymphatic and Immune system Composed of red bone marrow, thymus, spleen, lymph nodes, and lymphatic vessels Picks up fluid leaked from blood vessels and returns it to blood Disposes of debris in the lymphatic stream Houses white blood cells involved with immunity Respiratory system Composed of the nasal cavity, pharynx, trachea, bronchi, and lungs Keeps blood supplied with oxygen and removes carbon dioxide Digestive system Composed of the oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus, and liver Breaks down food into absorbable units that enter the blood Eliminates indigestible foodstuffs as feces Urinary system Composed of kidneys, ureters, urinary bladder, and urethra Eliminates nitrogenous wastes from the body Regulates water, electrolyte, and pH balance of the blood Male reproductive system Composed of prostate gland, penis, testes, scrotum, and ductus deferens Main function is the production of offspring Testes produce sperm and male sex hormones Ducts and glands deliver sperm to the female reproductive tract Female reproductive system Composed of mammary glands, ovaries, uterine tubes, uterus, and vagina Main function is the production of offspring Ovaries produce eggs and female sex hormones Remaining structures serve as sites for fertilization and development of the fetus Mammary glands produce milk to nourish the newborn Endocrine system Composed of hormone-producing glands and hormone-producing cells in several other organs Regulates body activities by releasing hormones, which are transported in blood to from an endocrine gland or tissue to a target organ

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BASIC ANATOMICAL TERMINOLOGY p.8 Anatomical Position: the subject stands erect facing the observer with the head level and the eyes facing forward. The feet are flat on the floor and directed forward, and the arms are at the sides with the palms facing forward.

Regional Names:

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These are terms given to specific regions of the body; important examples include head (cephalic), neck (cervical), trunk, upper limb, lower limb, etc.

Planes and Sections p. 10; fig. 1.3 - Sagittal plane: divides the body or organ into right and left sides. - Midsagittal plane (median plane): equal right and left sides. - Parasagittal plane: - Frontal (coronal) plane: into anterior and posterior portions. - Transverse plane: into superior (upper) and inferior (lower) portions. - Oblique plane: passes through the body or organ at an angle. Directional Terms p.12, 13; Exhibit 1.1, fig. 1.5 Superior and inferior ­ toward and away from the head, respectively Anterior and posterior ­ toward the front and back of the body Medial, lateral, and intermediate ­ toward the midline, away from the midline, and between a more medial and lateral structure Proximal and distal ­ closer to and farther from the origin of the body Superficial and deep ­ toward and away from the body surface Body Cavities: Study p.14; fig.1.6 Dorsal cavity protects the nervous system, and is divided into two subdivisions - Cranial cavity is within the skull and encases the brain - Vertebral cavity runs within the vertebral column and encases the spinal cord Ventral cavity houses the internal organs (viscera), and is divided into two subdivisions: thoracic and abdominopelvic Ventral Body Cavity Membranes Parietal serosa lines internal body walls Visceral serosa covers the internal organs Serous fluid separates the serosae Thoracic cavity is subdivided into pleural cavities, the mediastinum, and the pericardial cavity Pleural cavities ­ each houses a lung; the serous membrane of the pleural cavities is the pleura: visceral pleura and parietal pleura; serous fluid: lubrication. Mediastinum ­ contains the pericardial cavity, and surrounds the remaining thoracic organs, such as heart, thymus, esophagus, trachea, and large blood vessels. Pericardial cavity ­ encloses the heart; the serous membrane of the pericardial cavity is the pericardium: visceral and parietal. The abdominopelvic cavity is separated from the superior thoracic cavity by the dome-shaped diaphragm. It is composed of two subdivisions

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Abdominal cavity ­ contains the stomach, intestines, spleen, liver, and other organs; the serous membrane of the abdominal cavity is the peritoneum. Pelvic cavity ­ lies within the pelvis and contains the bladder, reproductive organs, and rectum Abdominopelvic Regions and Quadrants p.18 - Nine regions by 4 lines: o Subcostal and transtubular (horizontally) o Two midclavicular (vertically) - Right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right inguinal (iliac), hypogastric, and left inguinal (iliac). Representative structures found in the abdominopelvic regions. - Quadrants: Right upper quadrant (RUQ), left upper quadrant (LUQ), right lower quadrant (RLQ), and left lower quadrant (LLQ).

The Human Body and Disease 1. A disorder is any abnormality of structure and/or function. 2. A disease is a more specific term for an illness characterized by a recognizable set of symptoms (subjective changes in body function) and signs (objective changes that can be observed and measured). 3. Epidemiology is the study of how diseases are transmitted among individuals in a community. 4. Diagnosis is the science and skill of distinguishing one disorder or disease from another. E. Medical Imaging 1. A variety of medical imaging techniques are available to permit visualization of the interior of the human body; important techniques include the following (see Table 1.3): i. Radiography ii. Magnetic resonance imaging (MRI) iii. Computed tomography (CT) iv. Ultrasound Scanning v. Positron emission tomography (PET) vi. Radionuclide scanning vii. Endoscopy

Exercise I ORGAN SYSTEM REVIEW SHEET ________ The machines of the body; allows for movement of body part by their shortening or contraction. ________ A slow acting control system of the body; elicits a response via hormones. _______ Mechanically and chemically breaks down food; absorb breakdown products. _______ Pumps and propels blood, chemical messengers, hormones etc. throughout the body. _______ Serves as a barrier against infective agents; is also involved in the thermoregulation, sensory reception and vitamin D synthesis. _______ Allows for intake of oxygen and elimination of carbon dioxide; is also involved in regulating the acidity of the blood.

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_______ This system is designed for propagation of the species; consists of structures which houses sperm & eggs (as well as accessory ducts & glands) _______ Consists of a control center and peripheral receptors; responsible for fast acting regulation of bodily functions. _______ A system designed to remove liquid wastes from the body; additionally, it assists in regulating blood pressure, red blood formation, and the acid-base balance of the body. ______ Supports and assists in the movement of the body; it also protects internal organs, stores minerals & is the site of red blood cell formation. ______ A system consisting of glands, vessels and organs whose function is to participate in the immune response. a. Skeletal b. Cardiovascular c. Reproductive d. Urinary e. Integumentary f. Respiratory g. Digestive h. Nervous i. Endocrine j. Lymphatic k. Muscular Exercise II MEDICAL TECHNIQUES WORKSHEET 1. _______ Examination by application of hands/fingers to detect evidence of disease. 2. _______ Inspection of internal body organs and cavities using a scope and camera attached to a flexible tube. 3. _______ X ray technique which produces a cross sectional image in a selected plane of view; computer generated; provides a 3-D prospective with better resolution than conventional X-ray. 4. _______ To cut apart for study purpose 5. _______ Process of film exposure using X-ray passing through the body to obtain pictures of internal structure; dense tissue is better visualized; limited to 2-dimensions. 6. _______ Tissue sampling by excision for diagnostic examination. 7. _______ Large magnetic device which energizes (aligns) H atoms in tissue, and produces images from subsequent energy released by the process; non-ionizing method of inspection for soft tissue. 8. _______ Microscope examination with magnification in the 1,000 x. 9. _______ Sound waves striking tissue of different densities produce characteristic echoes, which can be recorded as image. 10. _______Visualizes metabolically active cells using radioactive glucose, thus providing information regarding tissue function; using computer-generated image provides a picture of living, working cell. a. palpation d. dissection g. biopsy j. endoscopy b. MRI e. PET scan h. radiography c. CT scan f. light microscopy i. Ultrasound

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LABORATORY IDENTIFICATION Nine regions - Right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right inguinal (iliac), hypogastric, and left inguinal (iliac). Quadrants: - Right upper quadrant (RUQ), left upper quadrant (LUQ), right lower quadrant (RLQ), and left lower quadrant (LLQ). Exercise: ORGAN AND BODY CAVITY IDENTIFICATION SHEET (on models) Organ Major Cavity Subdivision Body System A ­ anterior T- thoracic P - posterior AP ­ Abdominopelvic C ­ cranial 1. adrenal gland 2. brain 3. descending aorta Thoracic aorta Abdominal aorta 4. esophagus 5. gallbladder 6. heart 7. inferior vena cava 8. kidney 9. large intestine 10. liver 11. lung 12. pancreas 13. small intestine 14. spleen 15. stomach 16. trachea 17. urinary bladder 18. diaphragm -----------------------19. thyroid gland -----------------------20. larynx (thyroid cartilage) ------------------------

TRANSVERSE SECTIONS: 1. Neck: trachea esophagus 2. Thorax: heart esophagus 3. Abdomen: liver inferior vena cava

right lung right lung stomach

left lung left lung spleen

aorta aorta

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CELLS A GENERALIZED CELL 1. Plasma membrane 2. Nucleus 3. Cytoplasm: consists of Cytosol and Organelles.

CHAPTER 2 p.27

PLASMA MEMBRANE ­ Outer limiting membrane of the cell; boundary of cell, barrier between ECF and ICF Structure (fluid-mosaic model) ­ fluid sea ­ composed of a lipid bilayer of phospholipids (75%), cholesterol, and glycolipid with mosaic iceberg Embedded integral proteins, transmembrane proteins (glycoprotein), and peripheral proteins Functions 1. Barrier (selectively permeable) ­ actively regulates passage of substances through the membrane; lipid soluble substances are more permeable; dynamic, active structure which separates two types of fluid compartments (ICF- intracellular, ECF ­ extracellular) differing in ionic composition; proteins act as transporters for large water soluble molecules. 2. Functions of membrane proteins - Channel proteins: selectively allow a single type ion to pass through. - Transporters (carrier proteins): transport - Receptors: serve as cellular recognition sites for hormones, glucose. - Enzymes - Cell-identify markers (glycoproteins and glycolipids): i.e. ABO blood type markers. CYTOPLAM Cytosol - 75-90% of water plus dissolved and suspended components, such as ions, glucose, amino acids, fatty acids, proteins, lipids, ATP, and waste products. Organelles Cytoskeleton (skeletal and muscular systems of the cell) A. Microfilaments a. Structure ­ composed of the protein actin, the thinnest elements of cytoskeleton. b. Functions ­ movement (muscle contraction) and mechanical support (in microvilli). B. Intermediate filaments ­ examples: keratin filaments within epithelial skin cells, neurofilaments of neurons. C. Microtubules a. Structure ­ hollow tube-like structures formed from subunits termed tubulin, the largest of cytoskeleton components. b. Functions Centrosome ­ consists of pericentriolar material and centrioles. - Centrioles: a pair of cylindrical structures, each of which is composed of nine clusters of three microtubules.

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- Forming the mitotic spindle during cell division. Cilia: move fluids along cell's surface. Flagella: move an entire cell. Ribosomes a. Structure ­ composed of a large subunit and a small subunit. b. Types ­ as cluster of ribosomes in the cytoplasm (free ribosome, polysomes) or attached to the endoplasmic reticulum (rough ER). c. Function ­ Free ribosomes or polysomes: synthesis of proteins, which are used inside the cell. Rough ER ­ Endoplasmic reticulum (ER) ­ series of tubules and flattened stack of membrane (cisternae) located in the cytoplasm. Rough (granular) ER a. Structure ­ contains ribosomes attached to cisterna. b. Function ­ site of synthesis of proteins; Fate of proteins ­ move to Golgi apparatus for insertion into organelles (such as lysosomes) or secretory vesicle, which fuse with the plasma membrane and release the proteins into the ECF. Smooth (agranular) ER Structure ­ series of tubules lacking ribosomes Function ­ site of fatty acid, phospholipid, or steroid synthesis; detoxify chemicals; store and release calcium in muscle cells. Golgi complex (apparatus, body) a. Structure ­ series of flattened sacs termed cisternae with expanded ends and associated Golgi vesicles. b. Function ­ sorts, packages, and delivers cellular protein products to plasma membrane for eventual secretion; may add carbohydrates during the processing. Lysosomes a. Structure ­ round membrane covered structures containing digestive enzymes. b. Function ­ digestive system of cell; breakdown large substances in the cell; remove worn-out organelles (autophagy); destroy bacteria in phagocytic white blood cells; may destroy host cell (autolysis). Peroxisomes a. Structure ­ membranous sac containing oxidative enzymes; i.e. catalase. b. Function ­ removal of toxic substances such as oxygen radicals and hydrogen peroxide. Mitochondrion (plural ­ mitochondria) a. Structure ­ oval of round organelle containing two membranes; outer limiting membrane, and inner membrane containing folds termed cristae; central cavity called matrix. b. Function ­ powerhouse of cell; generates ATP through reactions of aerobic cellular respiration.

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Nucleus ­ brain of cell A. Nuclear envelope a. Structure ­ double membrane with pores. b. Function ­ separates nucleoplasm from cytoplasm; allows substances to pass between nucleus and cytoplasm through pores. B. Chromatin a. Structure ­ 46 long strands; composed of DNA and protein (histone); condenses into 46 chromosomes prior to cell division. b. Function ­ contain heredity information, which is coded in segments termed genes. C. Nucleoli (single, nucleolus) a. Structure ­ clusters of protein, DNA, and RNA that are not enclosed by a membrane. b. Function ­ site of synthesis (assembly) of ribosome.

LABORATORY IDENTIFICATION Identify the following structures on the microscope: 1. ocular (eyepiece) 2. nosepiece 3. objectives (scanning power, lower power, high power) 4. arm 5. base 6. mechanical stage 7. diaphragm lever 8. coarse adjustment knob 9. fine adjustment knob On the Cell model: 1. plasma membrane 4. lysosome 7. rough endoplasmic reticulum 9. nucleolus

2. mitochondrion 3. centrosome 5. Golgi complex 6. nuclear envelope 8. smooth endoplasmic reticulum 10. peroxisome

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LABORATORY ­ MICROSCOPE Name __________________________ Date ____________

FEATURES OF THE MICROSCOPE Identification: Identify the following structures on the microscope with your partner: ocular __ (eyepiece), nosepiece, objectives (scanning power __, lower power __, higher power __ ), arm, base, mechanical stage, diaphragm lever, coarse adjustment knob, fine adjustment knob, lamp. Diaphragm Lever ­ indicate the function of the diaphragm lever. Focusing ­ Describe the proper procedure for focusing material under the microscope. a. Rotate the nosepiece until the scanning power objective is in place. a. Place the microscope slide in the mechanical stage. Check to see that the slide is in contact with the base of the mechanical stage. Using the coaxial stage controls, center the material to be viewed. b. Using the coarse adjustment knob, move the upward towards the scanning objective until it reaches a stop. c. Now, while viewing through the ocular, move the stage downward away from the objective ­ using the coarse adjustment knob ­ until the material comes into focus. Regulate the amount of light entering the microscope by moving the diaphragm lever. d. To use other objectives, rotate the nosepiece until the objective is in place. Then refocus using the fine adjustment knob. Care of the Microscope ­ Carry the microscope with two hands. Always have the scanning objective in place before putting the microscope away. Wrap the cord around the top of the microscope. Total Magnification ­ To determine the total magnification of material viewed through the microscope, multiply the power of the ocular (10x) times the power of the respective objective. Scanning objective - ______ x ______ = ________ Low power objective - ______ x ______ = ________ High power objective - ______ x ______ = ________ The Inverted Image 1. Obtain a slide with the letter e mounted on it and place it right side up on the mechanical stage. 2. Using the focusing procedure, focus the e with scanning objective. 3. Draw the letter e as it appears when viewed through the microscope. _____________ 4. While view through the ocular, rotate the coaxial controls of the mechanical stage so that the slide moves to the right. In which direction does the e move while viewing the slide? ___________________ 5. While viewing through the ocular, rotate the coaxial controls so that the slide moves toward you. In which direction does the e move while viewing the slide? ______________________

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Estimate the diameter of the area of field of each objective using a slide that has 1 mm graph paper (each square is 1 square millimeter). Indicate the number of squares and approximate portion of any uncompleted square extending across the diameter. Do not move the slide when you count. 6. Scanning objective - _________ mm 7. Low power objective - _________ mm or _______ m 8. High power objective - _________ mm or _______ m (To determine high power values, divide each low power estimate by 4.0) B. MICROSCOPE EXAMINATION OF CHEEK CELLS The mucous membrane of the cheek contains several layers of cells, which are continuously replaced through cell division of the basal layers. The cells in the outer layer are alive, and may be easily collected, stained, and examined under the microscope. Procedure 1. Rub the inside of the cheek gently with side of a toothpick. 2. Rotate the toothpick in the center of a microscope slide to remove the cells. Spread the material about 2 cm across the slide. 3. Place one drop of methylene blue stain on the material. 4. Cover the drop with a cover slip. 5. Observer and diagram a cell under 100x and 400x magnification. Identify all prominent organelles and subcellular structures. 6. Approximate the Width of a Typical Cheek Cell ­ To approximate the width of a typical cell at high power, estimate the number of cheek cells, which could fit ­ side by side ­ along the diameter without moving the slide. Then divide the diameter of the area of field (determined previously A8) by your estimated number of cells. ______ m (area of field diameter) / (divide) _______ # (Estimated # of Cells) = _____(Approximate Size of Cheek Cell) C. MICROSCOPE EXAMINATION OF BLOOD CELLS ­ Obtain a blood smear slide. Using the high power objective, identify and diagram a representative red blood cell (RBC), and two different representative white blood cells (WBCs). 1. Representative RBC Representative WBCs

2. Distinguish between the general features of RBC and WBC. RBC WBC Size Number Presence of Organelles 3. Estimate the Width of a typical RBC and a WBC using the above procedure.

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Estimate size of a RBC ______ m (area of field diameter) / (divide) _______ # (Estimated # of Cells) = _____(Approximate Size of RBC) (Rather than using the entire diameter to estimate the number of RBCs, estimate the number of RBCs occupying ¼ of the diameter and multiple that numbers by 4). Estimate size of WBC ______ m (area of field diameter) / (divide) _______ # (Estimated # of Cells) = _____(Approximate Size of WBC) (Rather than using the entire diameter to estimate the number of WBCs, estimate the number of WBCs occupying ¼ of the diameter and multiple that numbers by 4). Compare the size of a representative WBC with a representative RBC. D. ORGANELLE IDENTIFICATION ­ on a cell model. 1. plasma membrane 4. lysosome 7. rough endoplasmic reticulum 9. nucleolus 2. mitochondrion 3. centrosome 5. Golgi complex 6. nuclear envelope 8. smooth endoplasmic reticulum 10. peroxisome

Initials of lab partner ________

Date ___________________

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TISSUES

CHAPTER 3

Types of Tissues and Their Origins 1. A tissue is a group of similar cells that usually have a common embryological origin and function together to carry out specialized activities. 2. The body is composed of four major families of tissues: i. Epithelial tissue covers body surfaces; lines hollow organs, body cavities, and ducts; it also forms glands. ii. Connective tissue protects and supports the body and its organs; binds organs together; stores energy reserves as fat; provides immunity. iii. Muscular tissue generates physical force for movement and thereby generates body heat. iv. Nervous tissue detects changes in a variety of conditions and responds by initiating and transmitting nerve impulses (signals) that help control and coordinate body activities. Cell Junctions 1. Cell junctions are points of contact between neighboring plasma membranes. 2. There are five major types of cell junctions: i. Tight junctions a. form tight seals between cells such as the epithelial cells that comprise the inner lining of the stomach, intestines, and urinary bladder b. these junctions prevent the passage of substances between cells ii. Adherens junctions a. strongly fasten cells to each other; they help epithelial surfaces resist separation iii. Desmosomes a. strongly fasten cells to each other; they prevent epidermal cells from separating under tension and cardiac muscle cells from pulling apart during contraction iv. Hemidesmosomes a. strongly anchor cells to an underlying basement membrane v. Gap junctions a. formed by minute, fluid-filled tunnels that permit passage of electrical signals or chemicals (i.e., ions and small molecules) from one cell to a neighboring cell b. located in some parts of the nervous system, in heart muscle, and in the gastrointestinal tract

EPITHELIAL TISSUE General features: - The cells are densely packed, little extracellular space. - Have various surfaces: lateral, apical (free surface), basal surfaces. - Basement membrane: a thin extracellular layer. - Avascular. - Has a very high rate of cell division - has a nerve supply - numerous functions including: protection, filtration, secretion, absorption, excretion

Divided into two major types: a. covering and lining epithelium b. glandular epithelium

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Covering and Lining Epithelium a. arrangement of cells into layers reflects its location and function b. arrangements include: i. Simple (unilaminar) epithelium (single layer of cells) ii. Pseudostratified epithelium (single layer that appears stratified) iii. Stratified (multilaminar) epithelium (two or more layers of cells) c. cells may be categorized by cell shape: i. Squamous cells are flattened ii. Cuboidal cells are usually cube-shaped or hexagons iii. Columnar cells are tall and cylindrical iv. Transitional cells are able to undergo changes in shape caused by distension e. according to number of layers present and cell shapes (in the apical layer),

Table 3.1 Simple Squamous Single layer of flattened cells with disc-shaped nuclei and sparse cytoplasm Functions: Diffusion and filtration Provide a slick, friction-reducing lining in lymphatic and cardiovascular systems Present in the kidney glomeruli, lining of heart, blood vessels, lymphatic vessels, and serosae Simple Cuboidal Single layer of cubelike cells with large, spherical central nuclei Function in secretion and absorption Present in kidney tubules, ducts and secretory portions of small glands, and ovary surface Simple Columnar Single layer of tall cells with oval nuclei; many contain cilia Goblet cells are often found in this layer Function in absorption and secretion Nonciliated type line digestive tract and gallbladder Pseudostratified Columnar Single layer of cells with different heights; some do not reach the free surface Nuclei are seen at different layers, may contain goblet cells and bear cilia. Function in secretion and propulsion of mucus by ciliary action Ciliated: trachea, most of upper respiratory tract Stratified squamous: Several layers of cells; cuboidal and columnar shape in deep layer; squamous cells form the apical layer and several layers deep to it keratinized- skin; non-keratinized ­ wet surface, i.e. mouth, tongue. Function: protection. Transitional Several cell layers, basal cells are cuboidal, surface cells are dome shaped Stretches to permit the distension of the urinary bladder Lines the urinary bladder, ureters, and part of the urethra Glandular Epithelium - A gland is a one or more cell that makes and secretes an aqueous fluid - Classified by: Site of product release ­ endocrine or exocrine Relative number of cells forming the gland ­ unicellular or multicellular

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Endocrine Glands Ductless glands that produce hormones Secretions include amino acids, proteins, glycoproteins, and steroids Exocrine Glands More numerous than endocrine glands Secrete their products onto body surfaces (skin) or into body cavities Examples include mucous, sweat, oil, and salivary glands - Classified as: Unicellular or Multicellular Simple or compound duct type Functional Classification: Merocrine glands: form the secretory product and release it from the cell, i.e. salivary glands. Apocrine glands: pinched off portion of cell is secretion, human? Holocrine glands: mature cell dies and becomes secretory product, i.e. sebaceous gland of the skin. CONNECTIVE TISSUE (CT) p.72 Found throughout the body; most abundant and widely distributed in primary tissues Connective tissue proper, Cartilage, Bone, Blood Functions of Connective Tissue Binding and support, Protection, Insulation, Transportation Characteristics of Connective Tissue Mesenchyme as their common tissue of origin One of the most abundant and widely distributed tissues Do not usually occur on free surfaces. Varying degrees of vascularity Nonliving extracellular matrix, consisting of ground substance and fibers Connective tissue cells: - Fibroblasts: present in all CT; secrete fibers and ground substance. - Macrophages: developed from monocytes; engulf bacteria and cellular debris. - Plasma cells: developed from B lymphocytes; secrete antibodies. - Mast cells: abundant alongside the blood vessels that supply CT; secrete histamine. - Adipocytes: deep to the skin and around organs such as heart and kidneys; store triglycerides. - White blood cells: not found in significant numbers in normal CT. Connective tissue extracellular matrix: 1. Ground substance: unstructured material that fills the space between cells o Support cells and binds them together. o Glycosaminoglycans (GAGs) ­ trap water. o Hyaluronic acid: a viscous, slippery substance that binds cells together. 2. Fibers: a. Collagen fibers: o Consists of protein collagen. o Very strong, but also flexible; provides high tensile strength o In most CT: bone, cartilage, tendon, and ligaments. b. Elastic fibers:

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o Consists of elastin, fibrillin. o Elasticity. o Plentiful in skin, blood vessel walls, and lung tissue. c. Reticular fibers: o Consists of collagen and a coating of glycoprotein. o Provide support and strength, also from Stroma of many soft organs, i.e. spleen. Classification of connective tissues: p.74 I. Embryonic connective tissue (see Table 3.3) A. Mesenchyme gives rise to all other connective tissues B. Mucous connective tissue (Wharton's jelly) is found primarily in the umbilical cord of the fetus II. Mature connective tissue (see Table 3.4) A. Loose connective tissue has loosely arranged fibers in the matrix i. Areolar connective tissue - has several types of cells including fibroblasts, macrophages, etc. - has all three types of fibers - ground substance is semifluid - located in subcutaneous layer of skin, blood vessels, etc. - provides strength, elasticity, and support ii. Adipose tissue - contains adipocytes that store triglycerides - located in subcutaneous layer, around organs, etc. - white adipose tissue insulates, stores energy reserves, supports and protects various organs; brown adipose tissue generates heat in the newborn iii. Reticular connective tissue - contains reticular fibers and reticular cells - binds together cells of smooth muscle tissue, forms stroma (framework) of organs, etc. B. Dense connective tissue has densely arranged fibers in the matrix i. Dense regular connective tissue - contains rows of fibroblasts located between numerous parallel (i.e., regularly arranged) bundles of collagen fibers - forms tendons and most ligaments - provides strong attachment between various structures ii. Dense irregular connective tissue - contains fibroblasts scattered among randomly oriented (i.e., irregularly arranged) collagen fibers - located in dermis, periosteum, heart valves, etc. - provides strength iii. Elastic connective tissue - contains fibroblasts scattered among elastic fibers - located in walls of elastic arteries, lung tissue, etc. - provides elasticity and strength

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C. Cartilage contains chondrocytes embedded in the lacunae (spaces) of a gelatinous matrix that includes collagen fibers and elastic fibers; it is avascular (and therefore heals slowly) and lacks nerves; it is usually covered by a perichondrium i. Hyaline cartilage - has fine collagen fibers that are not visible with ordinary staining techniques used in light microscopy - is most abundant (but weakest) type of cartilage - located on ends of long bones, nose, trachea, etc. - provides flexibility and support; at joints, it reduces friction and absorbs shocks ii. Fibrocartilage - contains visible bundles of collagen fibers, making it the strongest type of cartilage - it lacks a perichondrium - located in intervertebral discs, knee menisci, etc. - provides strength and rigidity as well as flexibility and support iii. Elastic cartilage - contains network of elastic fibers - located in epiglottis, external ear, etc. - maintains shape and provides strength and elasticity D. Bone (osseous) tissue contains osteocytes embedded in lacunae (with canaliculi) of a rigid, calcified matrix that includes collagen fibers; it is classified as: i. Compact (dense) bone composed of osteons (haversian systems) in which there are concentric rings of matrix called lamellae; each osteon contains a central (haversian) canal ii. Spongy (cancellous) bone consisting of trabeculae; spaces between the trabeculae contain red bone marrow. Bone supports, protects, helps generate movement, stores minerals, and houses red marrow and yellow marrow. E. Blood tissue consists of a liquid matrix called plasma in which the following formed elements are suspended: i. Erythrocytes (red blood cells) transport the gases oxygen and carbon dioxide ii. Leukocytes (white blood cells) are involved in phagocytosis, immunity, and allergic reactions iii. Platelets play a role in blood clotting F. Lymph is interstitial fluid that flows in lymphatic vessels. E. Membranes 1. An epithelial membrane consists of an epithelial layer and an underlying connective tissue layer. 2. The principal epithelial membranes are: a. Mucous membrane (mucosa) lines a cavity that opens to the exterior (e.g., gastrointestinal tract, respiratory tract, etc.); it forms a barrier against entry of

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microbes, secretes mucus to prevent dehydration and trap pathogens, etc.; the connective tissue layer is called lamina propria b. Serous membrane (serosa) lines (parietal layer) a body cavity that does not open to the exterior (e.g., thoracic cavity, abdominal cavity), and it covers (visceral layer) organs inside these cavities (e.g., lungs, stomach); the epithelial layer secretes a lubricating serous fluid that reduces friction between the organs and the walls of the cavities; examples include the pericardium, pleura and peritoneum. c. Cutaneous membrane (skin) is discussed in Chapter 5. 3. Synovial membranes (which lack an epithelial layer) line joint cavities, bursae, and tendon sheaths; synoviocytes secrete components of a lubricating synovial fluid that reduces friction during movements. F. Muscular Tissue 1. Muscular tissue consists of cells, usually called muscle fibers (myocytes), which are specialized to contract and therefore provide motion, maintain posture, and generate heat. 2. There are three major types (see Table 3.5): a. Skeletal muscle tissue is attached to bones and consists of long, cylindrical cells that are striated and multinucleate; it is under voluntary control b. Cardiac muscle tissue forms most of the wall of the heart and consists of striated, branching cells connected by intercalated discs; it is under involuntary control c. Smooth muscle tissue is located primarily in the walls of hollow internal organs (e.g., stomach, blood vessels, etc.) and consists of non-striated spindle-shaped cells; it is usually under involuntary control. G. Nervous Tissue 1. Nervous tissue consists of two major kinds of cells (see Table 3.6): a. Neurons detect stimuli, convert stimuli into action potentials (nerve impulses), and conduct these messages to other neurons, muscle fibers or glands; neurons consist of: i. cell body which contains the nucleus and most other organelles ii. branched processes called dendrites iii. process called axon which conducts nerve impulses away from the cell body b. Neuroglia provide protection and support to the neurons.

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LABORATORY IDENTIFICATION Epithelium: 1. 2. 3. 4. 5. 6.

Simple cuboidal epithelium Simple columnar epithelium Keratinized stratified squamous epithelium Non-keratinized stratified squamous epithelium Transitional epithelium Pseudostratified ciliated columnar epithelium

Connective Tissue: 1. Areolar Connective Tissue 2. Adipose Tissue 3. Dense regular Connective Tissue 4. Dense irregular Connective Tissue 5. Hyaline cartilage: Ground substance, lacuna, chondrocytes 6. Blood smear: red blood cells (erythrocytes), white blood cells (leukocytes) Do not abbreviate your answers on the laboratory practical.

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THE INTEGUMENTARY SYSTEM

CHAPTER 5

A. Introduction p.116 1. Tissues are organized to form an organ, and organs are organized to form systems. 2. The organs of the integumentary system include the skin and its accessory structures including hair, nails, and glands, as well as blood vessels, muscles and nerves. 3. Dermatology is the medical specialty for the diagnosis and treatment of disorders of the integumentary system. B. Structure of the Skin 1. The skin (cutaneous membrane) covers the body and is the largest organ of the body. 2. It consists of two major layers: i. outer, thinner layer called the epidermis ii. inner, thicker layer called the dermis 3. Beneath the dermis is a subcutaneous (subQ) layer (also called hypodermis) which attaches the skin to the underlying tissues and organs. 4. The epidermis has a number of important characteristics: i. the epidermis is composed of keratinized stratified squamous epithelium ii. it contains four major types of cells: a. 90% of the cells are keratinocytes, which produce keratin that provides protection b. melanocytes, which produce the pigment melanin that protects against damage by ultraviolet radaition c. Langerhans cells (or intraepidermal macrophage cells), which are involved in immune responses d. Merkel cells (or tactile epithelial cells), which function in the sensation of touch along with the adjacent tactile (or Merkel) discs iii. the epidermis contains four major layers (thin skin) or five major layers (thick skin); see Table 5.1: Epidermal Strata Stratum Description Basale Deepest layer where continuous cell division occurs which produces all the other (germinativum) layers; a single row of cuboidal or columnar keratinocytes; stem cells, all other three types of cells are scattered. Spinosum 8-10 rows of polyhedral keratinocytes; Melanocytes and Langerhans cells. Granulosum 3-5 rows of flattened keratinocytes: organelles begin to degenerate; contain granules Lucidum 3-4 rows of clear, flat, dead keratinocytes with keratin; in thick skin only. Corneum 25 ­ 30 rows of dead keratinocytes with keratin; continuously shed and replaced by cells from deeper strata From the superficial to the deepest layer: Can Little Girl Speak German? 5. The dermis has several important characteristics:

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i. the dermis is composed of connective tissue containing collagen and elastic fibers ii. the dermis contains two layers (see Table 5.2): a. the outer papillary region consists of areolar connective tissue containing thin collagen and elastic fibers, dermal papillae (including capillary loops), corpuscles of touch (Meissner's corpuscles), and free nerve endings b. the deeper reticular region consists of dense irregular connective tissue containing collagen and elastic fibers (which provide strength, extensibility, and elasticity to the skin), adipose cells, hair follicles, nerves, sebaceous (oil) glands, and sudoriferous (sweat) glands 6. Epidermal ridges reflect contours of the underlying dermal papillae and form the basis for fingerprints (and footprints); their function is to increase firmness of grip by increasing friction. 7. Variations in skin color arise from variations in the amounts of three pigments: i. melanin (located mostly in the epidermis, where it absorbs UV radiation) - albinism is an inherited inability to produce melanin - vitiligo is a condition in which there is a partial or complete loss of melanocytes ii. carotene (found in the stratum corneum, dermis, and subcutaneous layer) iii. hemoglobin (located in erythrocytes flowing through dermal capillaries) Cyanotic: occurs because hemoglobin is depleted of oxygen; skin appears bluish. Jaundice: is due to a buildup of the yellow pigment bilirubin the blood. 8. Subcutaneous (subQ) layer (also called hypodermis) -composed of adipose and areolar connective tissue; is not part of the skin but, among its functions, it attaches the skin to the underlying tissues and organs; this layer (and sometimes the dermis) contains lamellated (pacinian) corpuscles which detect external pressure applied to the skin. C. Accessory Structures of the Skin Hair (pili) have a number of important characteristics: i. the primary functions of hair are protection, reduction of heat loss, and sensing light touch ii. hair is composed of dead, keratinized epidermal cells iii. each hair consists of: a. shaft which mostly projects above the surface of the skin b. root which penetrates into the dermis c. hair follicle which surrounds the root; it consists of an epithelial root sheath which in turn is surrounded by a dermal root sheath iv. located at the base of a hair follicle is the bulb; it has an indentation called the papilla of the hair where blood vessels provide nourishment to the growing hair v. associated with hairs are sebaceous (oil) glands, arrector pili muscles, 4. Sebaceous (oil) glands have several important characteristics: i. they are typically connected to hair follicles ii. they secrete an oily substance called sebum which prevents dehydration of hair and skin, and inhibits growth of certain bacteria

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5. Sudoriferous (sweat) glands produce sweat (perspiration); there are two types of sweat glands (see Table 5.3): i. numerous eccrine (or merocrine) sweat glands which have an excretory duct that opens at a pore at the surface of the epidermis; the sweat secreted by these glands helps to cool the body by evaporating, and also eliminates small amounts of wastes - this sweat may be lost as insensible perspiration or sensible perspiration ii. apocrine sweat glands which are located mainly in the skin of the axilla, groin, areolae, and bearded facial regions of adult males; their excretory ducts open into hair follicles - this sweat is secreted during emotional stress and sexual excitement; it is commonly called cold sweat 6. Ceruminous glands are modified sweat glands located in the ear canal; along with nearby sebaceous glands, they are involved in producing a waxy secretion called cerumen (earwax) which provides a sticky barrier that prevents entry of foreign bodies into the ear canal. 7. Nails are composed of hard, keratinized epidermal cells located over the dorsal surfaces of the ends of fingers and toes. i. Each nail consists of: a. free edge b. transparent nail body (plate) with a whitish lunula at its base c. nail root embedded in a fold of skin ii. Associated with a nail are: a. hyponychium or nail bed (located under the free edge) attaches the nail to the fingertip b. eponychium (cuticle) attaches the margin of nail wall to neighboring epidermis c. nail matrix in which cell division occurs resulting in growth of the nail E. Functions of the Integumentary System Protection ­ chemical, physical, and mechanical barrier Body temperature regulation is accomplished by: Dilation (cooling) and constriction (warming) of dermal vessels Increasing sweat gland secretions to cool the body Cutaneous sensation ­ exoreceptors sense touch and pain Metabolic functions ­ synthesis of vitamin D in dermal blood vessels Blood reservoir ­ skin blood vessels store up to 5% of the body's blood volume Excretion ­ limited amounts of nitrogenous wastes are eliminated from the body in sweat Skin Cancer Most skin tumors are benign and do not metastasize A crucial risk factor for nonmelanoma skin cancers is the disabling of the p53 gene Newly developed skin lotions can fix damaged DNA The three major types of skin cancer are: Basal Cell Carcinoma Least malignant and most common skin cancer Stratum basale cells proliferate and invade the dermis and hypodermis Slow growing and do not often metastasize Can be cured by surgical excision in 99% of the cases

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Squamous Cell Carcinoma Arises from keratinocytes of stratum spinosum Arise most often on scalp, ears, and lower lip Grows rapidly and metastasizes if not removed Prognosis is good if treated by radiation therapy or removed surgically Melanoma Cancer of melanocytes is the most dangerous type of skin cancer because it is: Highly metastatic Resistant to chemotherapy Melanomas have the following characteristics (ABCD rule) A: Asymmetry; the two sides of the pigmented area do not match B: Border is irregular and exhibits indentations C: Color (pigmented area) is black, brown, tan, and sometimes red or blue D: Diameter is larger than 6 mm (size of a pencil eraser) Treated by wide surgical excision accompanied by immunotherapy Chance of survival is poor if the lesion is over 4 mm thick Burns - Tissue damage caused by excessive heat, electricity, radioactivity, or corrosive chemicals that destroy the proteins in the skin cells. Degrees: First degree: - Involved only the epidermis. - Mild pain, erythema but no blisters; skin functions remain intact. Second degree: - Destroys a portion of the epidermis and possible parts of the dermis. - Redness, blister, edema, and pain; some functions lost. Third degree: - Destroys a portion of the epidermis, the underlying dermis, and associated structures. - Most functions lost. Estimation of burning area: Rule of the Nines. Systemic effects: 1. A large loss of water, plasma, and plasma proteins 2. Bacterial infection 3. Reduced circulation of blood 4. Decreased production of urine 5. Diminished immune response

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LABORATORY IDENTIFICATION Integument (skin) models: 1. Epidermis: Stratum corneum Stratum Lucidum Stratum Granulosum Stratum Spinosum Stratum Basale (Germinativum) 2. Dermis: Papillary region Reticular region Dermal papillae 3. Subcutaneous layer (hypodermis) 4. Hair: Hair follicle, hair root, hair shaft, and arrector pili muscle 5. Sebaceous gland 6. Sudoriferous gland: Eccrine (merocrine) sweat gland Apocrine sweat gland 7. Cutaneous receptors Corpuscle of touch (Meissner corpuscle) Lamellated (Pacinian) corpuscle Microscopic slides of the skin: 1. Epidermis: Stratum corneum Stratum Lucidum Stratum Granulosum Stratum Spinosum Stratum Basale (Germinativum) 2. Dermis 3. Subcutaneous layer (hypodermis) 4. Melanocytes: identify melanocytes in heavily pigmented skin.

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BONE TISSUE

CHAPTER 6

Function of Bones p.141 Support ­ form the framework that supports the body and cradles soft organs Protection ­ provide a protective case for the brain, spinal cord, and vital organs Movement ­ provide levers for muscles Mineral storage ­ reservoir for minerals, especially calcium and phosphorus Blood cell formation ­ hematopoiesis occurs within the red bone marrow Triglyceride storage: in yellow bone marrow Types of Bones Long bones: femur, tibia, fibula, and humerus. Short bones: cube-shaped; carpal bones. Flat bones: cranial bones, sternum, scapular; has external and internal tables (compact bone) enclosing a layer of spongy bone called diploe. Irregular bones: certain facial bones, vertebrae, and calcaneus. Sesamoid bones: develop in certain tendons where there is considerable friction, tension, and stress; patellae. ANATOMY OF A BONE Structure of Long Bone 1. Diaphysis Tubular shaft that forms the axis of long bones Composed of compact bone that surrounds the medullary cavity Yellow bone marrow (fat) is contained in the medullary cavity 2. Epiphyses Expanded ends of long bones Exterior is compact bone, and the interior is spongy bone Joint surface is covered with articular (hyaline) cartilage Epiphyseal line separates the diaphysis from the epiphyses 3. Metaphyses: In a mature bone- the regions where the diaphysis joins the epiphyses In a growing bone ­ include the epiphyseal plate which is a layer of hyaline cartilage that allows the Diaphysis of the bone to grow in length, but not in width; Epiphyseal line: bone growth in length stops 4. Articular cartilage Hyaline cartilage; reduces friction and absorbs shock at freely movable joint; lacks a perichondrium, repair of damage is limited. 5. Periosteum ­ double-layered protective membrane Outer fibrous layer is dense irregular connective tissue Inner osteogenic layer is composed of osteoblasts and osteoclasts Richly supplied with nerve fibers, blood, and lymphatic vessels, which enter the bone via nutrient foramina Secured to underlying bone by perforating (Sharpey's) fibers 6. Medullary (marrow) cavity: contains fatty yellow bone marrow in adults. 7. Endosteum: lines the cavity; contains bone-forming cells.

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Bone Surface Markings 1. The surfaces of bones have surface markings (or osseous landmarks), structural features that are adapted to specific functions; the two major types of surface markings are: i. depressions and openings ii. processes

2.

Bone Surface Markings Bulges, depressions, and holes that serve as: Sites of attachment for muscles, ligaments, and tendons Joint surfaces Conduits for blood vessels and nerves Projections ­ Sites of Muscle and Ligament Attachment Tuberosity ­ rounded projection Crest ­ narrow, prominent ridge of bone Trochanter ­ large, blunt, irregular surface Line ­ narrow ridge of bone Tubercle ­ small rounded projection Epicondyle ­ raised area above a condyle Spine ­ sharp, slender projection Process ­ any bony prominence Projections That Help to Form Joints Head ­ bony expansion carried on a narrow neck Facet ­ smooth, nearly flat articular surface Condyle ­ rounded articular projection Ramus ­ armlike bar of bone Depressions and Openings Meatus ­ canal-like passageway Sinus ­ cavity within a bone Fossa ­ shallow, basinlike depression Groove ­ furrow Fissure ­ narrow, slitlike opening Foramen ­ round or oval opening through a bone

Bone or osseous tissue contains abundant matrix surrounding widely separated cells. The matrix of this connective tissue contains abundant mineral salts, primarily hydroxyapatite and some calcium carbonate, deposited in a framework of collagen fibers; these features give bone two important characteristics: i. calcification of bone tissue gives bone hardness ii. collagen fibers (and other organic molecules) give bone flexibility and tensile strength There are four major types of cells present:

HISTOLOGY OF BONE TISSUE

1. Osteogenic cells: unspecialized stem cells; the only bone cells to undergo cell division; develops into osteoblasts. 2. Osteoblasts: bone-building cells; form bone matrix. 3. Osteocytes: derived from osteoblasts; are mature bone cells; maintains bone tissue. 4. Osteoclasts: derived from the fusion of many Monocytes, functions in resorption, the destruction of bone matrix.

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There are two major classes of bone tissue:

Compact Bone Tissue

forms the external layer of all bones; provides protection and support and helps bones resist stress

-

-

Arranged in units called Osteons (Haversian systems). Central canal run longitudinally through the bone. Around the canals are concentric lamellae. Between the lamellae are small spaces called lacunae that contain osteocytes. Canaliculi: filled with extracellular fluid, fingerlike processes of osteocytes. Blood vessels, lymphatic vessels, and nerves from the Periosteum penetrate the compact bone through transverse perforating (Volkmann's) canals. The areas between osteons contain interstitial lamellae; outer circumferential lamellae just beneath the Periosteum; inner circumferential lamellae encircle the medullary cavity.

Spongy Bone Tissue - Consists of lamellae that are arranged in an irregular lattice of thin columns of bone called trabeculae. - In short, flat, and irregularly shaped bones; most of the epiphyses; a narrow rim around the medullary cavity. - contains spaces that are sometimes filled with red bone marrow

Blood and Nerve Supply 1. Bones have a rich blood supply; portions of bone containing red bone marrow have an especially rich supply of blood vessels. 2. Blood supply to a bone is provided by the following arteries (and accompanying veins): i. periosteal arteries ii. nutrient artery that enters a bone via a nutrient foramen iii. metaphyseal arteries iv. epiphyseal arteries 3. Nerve supply to a bone consists primarily of nerves to blood vessels and sensory nerves

(concerned with pain) supplying the periosteum BONE FORMATION Intramembranous Ossification - Bone forms directly within Mesenchyme arranged in sheet-like layers that resemble membranes. - The flat bones of the skull and mandible. Endochondral ossification - The formation of bone within hyaline cartilage that develops from mesenchyme. Steps: Development of the cartilage model. - Mesenchymal cells crowd together chondroblasts that produce a cartilage matrix a hyaline cartilage model is formed. - Perichondrium develops. Growth of the cartilage model. - Chondroblasts chondrocytes: cell division, further secretion of matrix. - Calcification of chondrocytes in the midregion of the model; mainly due to the burst of chondrocytes (hypertrophy) that release their contents and increase the pH of the matrix. Development of the primary ossification center. - Occurs in the shaft or diaphysis of the long bone, prior to birth.

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-

A nutrient artery penetrates the perichondrium, stimulating osteogenic cells to differentiate into osteoblasts, and then a bony collar around the shaft is formed. - The perichondrium around the diaphysis converted to a Periosteum - Medullary cavity. Development of secondary ossification centers. - In the epiphyses, around the time of birth. - No medullary cavity is formed; spongy bone remains. Formation of articular cartilage and epiphyseal plate. Bone Growth in Length and Thickness 1. Lengthening of a bone occurs at an epiphyseal plate, which consists of four regions: i. zone of resting cartilage ii. zone of proliferating cartilage iii. zone of hypertrophic cartilage iv. zone of calcified cartilage 2. Growth in bone diameter occurs via appositional growth, a process in which osteoblasts from the periosteum add new bone tissue to the outer surface. 3. Ossification of most bones is usually completed by age 25. Bone Remodeling 1. Bone remodeling is a continuous process in which worn and injured bone tissue is replaced by new bone tissue.

2. Osteoclasts resorb old bone tissue (bone resorption) and osteoblasts form the new bone tissue (bone deposition).

Bone Fractures (Breaks) Types of Bone Fractures - Open (compound) fracture vs. closed (simple) - Comminuted: bone fragments into three or more pieces; common in the elderly - Greenstick: incomplete fracture where one side of the bone breaks and the other side bends; occurs only in children - Impacted fracture: One end of fractured bone is force-fully driven into the interior of the other. - Pott's fracture: Fracture of the distal end of fibula - Colles' fracture: Fracture of the distal end of radius Stages in the Healing of a Bone Fracture 1. Hematoma formation Torn blood vessels hemorrhage A mass of clotted blood (hematoma) forms at the fracture site Site becomes swollen, painful, and inflamed 2. Fibrocartilaginous callus forms Granulation tissue (soft callus) forms a few days after the fracture Capillaries grow into the tissue and phagocytic cells begin cleaning debris The fibrocartilaginous callus forms when: Osteoblasts and fibroblasts migrate to the fracture and begin reconstructing the bone Fibroblasts secrete collagen fibers that connect broken bone ends

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Osteoblasts begin forming spongy bone Osteoblasts furthest from capillaries secrete an externally bulging cartilaginous matrix that later calcifies 3. Bony callus formation New bone trabeculae appear in the fibrocartilaginous callus Fibrocartilaginous callus converts into a bony (hard) callus Bone callus begins 3-4 weeks after injury, and continues until firm union is formed 2-3 months later 4. Bone remodeling

Normal bone growth, bone remodeling, and bone repair are dependent on the presence of: i. several minerals (e.g., calcium, phosphorus, etc.) ii. several vitamins (e.g., C, A, and D) iii. weight-bearing exercise iv. several hormones (e.g., human growth hormone, sex hormones, etc.)

APPLICATIONS TO HEALTH Osteomalacia Bones are inadequately mineralized causing softened, weakened bones Main symptom is pain when weight is put on the affected bone Caused by insufficient calcium in the diet, or by vitamin D deficiency Rickets Bones of children are inadequately mineralized causing softened, weakened bones Bowed legs and deformities of the pelvis, skull, and rib cage are common Caused by insufficient calcium in the diet, or by vitamin D deficiency Osteoporosis Group of diseases in which bone reabsorption outpaces bone deposit Spongy bone of the spine is most vulnerable Occurs most often in postmenopausal women Bones become so fragile that sneezing or stepping off a curb can cause fractures Osteoporosis: Treatment Calcium and vitamin D supplements Increased weight-bearing exercise Hormone (estrogen) replacement therapy (HRT) slows bone loss Natural progesterone cream prompts new bone growth Statins increase bone mineral density Osteomyelitis An infection of bone: high fever, pain, nausea, and edema. Often caused by bacteria, Staphylococus aureus. Osteopenia Reduced bone mass due to a decrease in the rate of bone synthesis.

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LABORATORY IDENTIFICATION AXIAL SKELETON (80 BONES) Axial skeleton ­ bones of the skull, vertebral column, and rib cage 1. Skull (includes cranium, facial bones, ear ossicles) ­ 28 bones. Cranium (8): frontal, occipital, ethmoid, sphenoid, 2 temporal, 2 parietal. Facial bones (14): 2 maxilla, 2 zygomatic, 2 lacrimal, 2 nasal 2 palatine, 2 inferior nasal concha, 1 mandible, 1 vomer. Ear ossicles (6): 2 malleus, 2 incus, 2 stapes. 2. Vertebral Column - 26 bones: 7 cervical, 12 thoracic, 5 lumbar, 1 sacrum, 1 coccyx. 3. Ribs - 24 bones 4. Sternum ­ 1 bone 5. Hyoid ­ 1 bone APPENDICULAR SKELETON (126 BONES) Appendicular skeleton ­ bones of the upper and lower limbs, shoulder, and hip 1. Upper Limb Region Pectoral Girdle Bones clavicle (2) scapula (2) humerus (2) 2. Lower Limb Region Pelvic Girdle Bones hip, pelvic or coxal (2)

Arm

Thigh Knee Leg

femur (2) patella (2) tibia (2) fibula (2) tarsals (7x2) metatarsals (5x2) Phalanges (14x2)

Forearm

radius (2) ulna (2) carpals (8x2) metacarpals (5x2) phalanges (14x2)

Hand

Foot

LONG BONE (longitudinal section): Diaphysis Epiphysis Compact bone Spongy bone

Medullary cavity

COMPACT BONE 1. Osteon model: osteon, central canal, lamellae (concentric, interstitial, and circumferential), lacunae, osteocytes, canaliculi, perforating ((Volkmann's) canal, periosteum, endosteum. 2. Microscope slides: osteon, central canal, osteocytes, canaliculi.

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JOINTS

CHAPTER 9

JOINTS CLASSIFICATIONS p.250 Introduction 1. A joint or articulation or arthrosis is a point of contact between neighboring bones, between bone and cartilage, or between bone and teeth. 2. Arthrology is the study of joints; kinesiology is the study of motion of the body.

Ligaments are dense irregular or dense regular connective tissue structures that bind one bone to another bone.

A sprain is the forcible wrenching or twisting of a joint that stretches or tear its ligaments but does not dislocate the bones. A strain is stretched of partially torn muscle. Based on structures: 1. Fibrous: the bones are held together by fibrous CT; no synovial cavity. 2. Cartilaginous: held together by cartilage, no synovial cavity. 3. Synovial: united by the dense irregular CT of an articular capsule; has a synovial cavity. Based on the degree of movement: Synarthrosis: an immovable joint. Amphiarthrosis: a slightly movable joint. Diarthrosis: a freely movable joint. All diarthroses are synovial joints. SYNOVIAL JOINTS Synovial cavity Articular cartilage: hyaline cartilage provides a smooth, slippery surface. Articular capsule: the outer fibrous capsule: dense irregular CT. The inner synovial membrane: areolar CT. Synovial fluid: secreted by the synovial membrane, functions are: lubrication, supply nutrients and remove wastes for cartilages, phagocytic cells remove microbes and the debris. Accessory ligaments (extracapsular and intracapsular) and articular disc Bursae and Tendon sheaths: not strictly parts of synovial joints. The fluid-filled bursal sacs cushion the movement; tendon sheaths reduce friction. MOVEMENTS AT SYNOVIAL JOINTS Gliding Movements One flat bone surface glides or slips over another similar surface Examples ­ intercarpal and intertarsal joints, and between the flat articular processes of the vertebrae Angular Movement Flexion -- bending movement that decreases the angle of the joint Extension -- reverse of flexion; joint angle is increased Dorsiflexion and plantar flexion -- up and down movement of the foot Abduction -- movement away from the midline Adduction -- movement toward the midline Circumduction -- movement describes a cone in space

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Rotation -- The turning of a bone around its own long axis; examples: Between first two vertebrae Hip and shoulder joints Special Movements Supination and pronation Inversion and eversion Protraction and retraction Elevation and depression Opposition Monaxial: motion around a single axis, i.e. hinge joint. Biaxial: side-to-side and up-and-down movements; i.e. condyloid joint. Triaxial: permit movement around three axes plus all directions in between, i.e. hip, shoulder joints. Summary of Joints: Structural Category Description Fibrous Suture Syndesmosis Interosseous membrane

Functional Classification Synarthrosis Amphiarthrosis Amphiarthrosis

Example Frontal suture Distal tibiofibular Between tibia and fibula

Cartilaginous Synchondrosis Synarthrosis Epiphyseal plate Symphysis Amphiarthrosis All symphyses occur in the midline of the body: intervertebral joints, pubic symphysis. Synovial Planar Diarthrosis Many biaxial, side-to-side, gliding Monaxial, flexion-extention Monaxial, rotation

intercarpal, intertarsal, Sternocostal Elbow, and knee, interphalangeal Atlantoaxial

Hinge

Pivot Condyloid

Biaxial, Radiocarpal, flexion-extention metacarpophalangeal (2nd to 5th). Abduction-adduction Triaxial, between trapezium and 1st flexion-extention metacarpal. Abduction-adduction, rotation Tritiaxial Shoulder and hip joints flexion-extention Abduction-adduction, circumduction, rotation

Saddle

Ball-and socket

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LABORATORY IDENTIFICATION For each of the following joints, indicate the following features: The specific type of synovial joint The type of axes All of the movements occurring at the joint Joint Shoulder (glenohumeral) Specific Type Type of axes Movements

Elbow (humeroulnar) Radioular (Between radius & ulna) Wrist (radiocarpal) Metacarpophalangeal (Between metacarpals & phalanges) Interphalangeal (Between phalanges) Hip

Knee

Atlanto-axial (Between C1 and C2 vertebrae)

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NERVOUS TISSUE

A. Overview of the Nervous System

CHAPTER 17

1. 2. 3.

4.

p.567 The nervous system and the endocrine system are the body's major control and integrating centers. Neurology is the study of the normal functioning and disorders of the nervous system. The major components of the nervous system include the brain, cranial nerves (and their branches), spinal cord, spinal nerves (and their branches), ganglia, enteric plexuses, and sensory receptors - a nerve is a bundle of axons (plus associated connective tissue and blood vessels) located outside the brain and spinal cord - ganglia are small masses of nervous tissue, consisting primarily of neuron cell bodies, that are located outside the brain and spinal cord - enteric plexuses are networks of neurons located in the walls of GI tract organs; they help regulate digestive system activities - sensory receptors are structures that monitor changes in the internal and external environment The nervous system has three major functions: i. sensory function, i.e., sensory receptors detect stimuli in the internal and external environments, resulting in sensory information being transmitted by sensory or afferent neurons to the brain or spinal cord ii. integrative function, i.e., interneurons play a role in analyzing the sensory information to provide perception, storing some of it, and making decisions regarding appropriate behaviors iii. motor function, i.e., motor or efferent neurons respond to integration decisions by initiating actions in effectors, including muscle fibers and glandular cells

B. Organization of the Nervous System

1. The nervous system consists of two major divisions: i. central nervous system (CNS), which consists of the brain and spinal cord ii. peripheral nervous system (PNS), which consists of [1] cranial nerves that emerge from the brain, and [2] spinal nerves that emerge from the spinal cord - the PNS contains [a] sensory or afferent neurons which transmit nerve impulses from sensory receptors to the CNS, and [b] motor or efferent neurons which transmit nerve impulses from the CNS to muscles and glands - the PNS is divided into three major subdivisions: a. voluntary somatic nervous system (SNS), which consists of [1] somatic sensory neurons that transmit information (input) from somatic and special sensory receptors to the CNS, and [2] somatic motor neurons that transmit messages (output) from the CNS to skeletal muscles b. involuntary autonomic nervous system (ANS), which consists of [1] autonomic (visceral) sensory neurons that transmit information from visceral receptors to the CNS, and [2] autonomic motor neurons that transmit

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messages from the CNS to smooth muscle, cardiac muscle, and glands; the motor portion of the ANS consists of two branches: I. sympathetic division which generally supports exercise and emergency actions, i.e., fight-or-flight responses II. parasympathetic division which generally promotes rest-anddigest activities c. involuntary enteric nervous system (ENS; the brain of the gut) which consists of neurons in the enteric plexuses that extend the entire length of the GI tract; the sensory neurons monitor changes in the GI tract and the motor neurons help regulate digestive system activities

C. Histology of Nervous Tissue

1. The nervous system consists of two major types of cells: i. neurons, which perform most of the specialized functions of the nervous system ii. neuroglia, which support, nourish, and protect the neurons and maintain the interstitial fluid that bathes neurons 2. Neurons: i. Neurons (or nerve cells) have excitability, the ability to respond to a stimulus and convert it into a nerve impulse (action potential). ii. Neurons range in length from less than 1 mm to greater than 1 meter, and they transmit nerve impulses at speeds that range from 0.5 to 130 meters per second. 3. Parts of a Neuron: i. Most neurons have three major parts: a. cell body (or soma or perikaryon) contains the nucleus surrounded by cytoplasm that includes typical organelles as well as: - lipofuscin pigment granules - Nissl bodies: for high levels of protein synthesis - neurofibrils and microtubules extending away from the cell body are extensions called nerve fibers including: b. dendrites are usually short, tapering, unmyelinated, and highly branched processes that emerge from the cell body - the dendrites are the receiving or input portion of a neuron c. axon is a long, thin cylindrical process that may be myelinated and transmits nerve impulses away from the cell body; it has several notable features: - joins the cell body at the axon hillock - the first portion of the axon is called the initial segment - except in sensory neurons, nerve impulses are initiated at the trigger zone (at the junction of the axon hillock and initial segment) - axon collaterals may branch off the axon - the axon and its axon collaterals end at many fine processes called axon terminals - the tips of some axon terminals are bulbous synaptic end bulbs (synaptic boutons), whereas others exhibit a string of swollen bumps called varicosities

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- synaptic end-bulbs and varicosities contain synaptic vesicles that store neurotransmitter molecules - most axons are myelinated, i.e., are surrounded by a myelin sheath ii.. The junction between two neurons is a synapse

- the presynaptic neuron transmits nerve impulses toward the synapse and the postsynaptic cell is a postsynaptic neuron or a muscle cell or a gland cell that

receives the signal - the synapse between a motor neuron and a muscle fiber is called a neuromuscular junction - the synapse between a neuron and a glandular cell is called a neuroglandular junction - the small gap between cells at a synapse is called the synaptic cleft; the presynaptic neuron releases neurotransmitters into the synaptic cleft which act on the postsynaptic cell - There are numerous neurotransmitters including acetylcholine (ACh), glutamate, aspartate, GABA, glycine, norepinephrine (NE), dopamine (DA), serotonin, endorphins, nitric oxide (NO), etc. 4. Structural Diversity in Neurons: i. There is great variation in the size and shape of neurons: a. cell bodies range in diameter from 5 to 135 micrometers b. the pattern of dendritic branching is quite variable and distinctive for neurons in different regions of the nervous system c. a few small neurons lack an axon and many others have very short axons; long neurons have axons that may exceed 1 meter in length 5. Classification of Neurons: i. Neurons may be classified according to both structural and functional features. ii. Structural classification is based on the number of processes that extend from the cell body: a. multipolar neurons usually have several dendrites and one axon; most neurons in the brain and spinal cord are of this type b. bipolar neurons have one main dendrite and one axon; these are located in the retina, inner ear, and olfactory area of the brain c. unipolar neurons are sensory neurons have just one process extending from the cell body; this process is essentially an axon with dendrites at its peripheral end iii. Among the many types of neurons are: a. Purkinje cells in the cerebellum b. pyramidal cells in the cerebral cortex 6. Neuroglia or Glia i. Neuroglia occupy about half the volume of the CNS; they are generally smaller but are more numerous than neurons. ii. Unlike neurons, neuroglia do not transmit nerve impulses and they can divide in the mature nervous system; brain tumors derived from glia are called gliomas. iii. There are four types of neuroglia in the CNS:

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a. astrocytes are star-shaped cells (with many processes) that perform several functions in support of neurons - they are the most numerous of the neuroglia - there are 2 types: - protoplasmic astrocytes located in the gray matter - fibrous astrocytes located mainly in white matter b. oligodendrocytes have few processes and produce a myelin sheath; each oligodendrocyte can myelinate parts of several axons c. microglia are small, phagocytic neuroglia that protect the nervous system by engulfing microbes and removing debris of dead cells d. ependymal cells line the brain ventricles and the central canal of the spinal cord; they secrete and aid in the circulation of cerebrospinal fluid and they form the blood-cerebrospinal fluid barrier iv. There are two types of neuroglia in the PNS: a. Schwann cells (or neurolemmocytes) produce the myelin sheaths around PNS axons; - each Schwann cell wraps about 1 mm of a single axon's length - the outer nucleated cytoplasmic layer of the Schwann cell is the neurolemma - gaps in the myelin sheath are called nodes of Ranvier - satellite cells surround the cell bodies of neurons in PNS ganglia v. Axons that lack a myelin sheath are said to be unmyelinated. Myelin Sheath Whitish, fatty (protein-lipoid), segmented sheath around most long axons It functions to: Protect the axon Electrically insulate fibers from one another Increase the speed of nerve impulse transmission Myelin sheath: produced by Schwann cells in PNS, oligodendrocytes in CNS. Neurolemma: The outer nucleated cytoplasmic layer of Schwann cell, in PNS only. Nodes of Ranvier: Gaps in the myelin sheath. 7. Gray and White Matter: i. The CNS has some regions that appear white and others that appear gray. ii. White matter is aggregations of unmyelinated and myelinated axons (that have myelin which gives this tissue a white color). iii. Gray matter contains neuronal cell bodies, dendrites, unmyelinated axons, axon terminals, and neuroglia, all of which are unmyelinated (therefore, gray color). iv. In the spinal cord, white matter surrounds a butterfly-shaped (in cross section) core of gray matter. v. In the brain, a thin layer of gray matter covers the cerebrum and cerebellum; the brain also contains numerous masses of gray matter called nuclei which consist of clusters of neuronal cell bodies. vi. Most nerves and all tracts are composed of white matter. D. Neural Circuits

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1. The CNS contains billions of neurons organized into complex networks called neural circuits, each having its own function. i. In a simple series circuit, a presynaptic neuron transmits a message to a single postsynaptic neuron, which in turn stimulates another neuron, and so on. ii. Most neural circuits are more complex: a. diverging circuit in which a presynaptic neuron forms synapses with several postsynaptic cells (i.e., divergence)

b. converging circuit in which several presynaptic neurons form synapses with a single postsynaptic neuron (i.e., convergence)

Somatic Senses and Motor Control

chapter 21, p. 678

A sensation is the conscious or subconscious awareness of changes in the external or internal conditions of the body. For a sensation to arise, four events typically occur: i. a stimulus capable of activating specific sensory neurons must occur ii. a sensory receptor or sense organ must respond to the stimulus and transduce (convert) it into a nerve impulse

iii. nerve impulses are conducted to the brain

iv. a region of the brain must receive and integrate the nerve impulses, producing a sensation Sensations can be grouped into two classes: i. general senses, which include both somatic senses (which include touch, pressure, vibration, warm, cold, pain, and proprioceptive sensations) and visceral senses ii. special senses, which include smell, taste, vision, hearing, and equilibrium (balance). ii. by type of energy receptors respond to: - photoreceptors detect light in the eye - mechanoreceptors detect mechanical pressure or stretching - thermoreceptors detect changes in temperature - osmoreceptors detect the osmotic pressure of body fluids - chemoreceptors detect specific chemicals

- nociceptors or pain receptors detect pain, usually as a result of damage to tissues

Somatic Sensory Pathways 1. Somatic sensory pathways relay information from somatic receptors to the primary somatosensory areas in the cerebral cortex and to the cerebellum; the pathways to the cerebral cortex consist of thousands of sets of three neurons: i. first-order neurons carry signals from somatic receptors into the brain stem or spinal cord via cranial nerves or spinal nerves ii. second-order neurons carry signals from the spinal cord and brain stem to the thalamus; axons of second-order neurons decussate to the opposite side before ascending to the thalamus

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iii. third-order neurons project from the thalamus to the primary somatosensory areas where conscious perception of sensations results

2. There are two general pathways by which somatic sensory signals entering the spinal

cord ascend to the cerebral cortex (see Table 21.3): i. posterior column-medial lemniscus pathways:

a. transmit nerve impulses for conscious proprioception and most tactile sensations

b. axons of the first-order neurons form the posterior (dorsal) columns in each side of the spinal cord c. axons of the second-order neurons decussate in the medulla and enter the medial lemniscus which is a projection tract that extends from the medulla to the thalamus d. third-order neurons project from the thalamus to the primary somatosensory area e. impulses conducted along this pathway give rise to the following sensations: - fine touch - stereognosis - proprioception and kinesthesia - weight discrimination - vibratory sensations

ii. anterolateral (or spinothalamic) pathways:

a. transmit nerve impulses for pain and temperature as well as for tickle, itch, crude touch, pressure and vibrations b. axons of the first-order neurons enter the spinal cord and synapse with second-order neurons in the posterior gray horns c. axons of second-order neurons decussate and ascend to the brain stem in either: - lateral spinothalamic tract which conveys impulses for pain and temperature - anterior spinothalamic tract which conveys impulses for tickle, itch, crude touch, pressure and vibrations d. axons of second-order neurons enter the thalamus and synapse with third-order neurons which project to the primary somatosensory area 3. The primary somatosensory area in each parietal lobe has been mapped out: i. some parts of the body are represented by large areas while other parts of the body are represented by small areas in the primary somatosensory cortex 4. Proprioceptive information reaches the cerebellum via two pathways: i. posterior spinocerebellar tract ii. anterior spinocerebellar tract

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D.

Somatic Motor Pathways 1. Both direct and indirect motor pathways extend from the cerebral cortex to skeletal muscles. 2. Motor cortex: i. the primary motor area (located in the precentral gyrus) of the cerebral cortex is the major control region for initiation of voluntary movements ii. the adjacent premotor area and the primary somatosensory area also contribute fibers to the descending motor pathways 3. Direct motor pathways: (see Table 21.4) i. voluntary motor impulses are transmitted from the motor cortex to somatic efferent neurons that innervate skeletal muscles via the direct motor (or pyramidal) pathways ii. These pathways consists of the following neurons: a. upper motor neurons (UMNs) whose axons descend into the medulla, where most of the axons decussate (the remaining ones decussate at lower levels), and terminate in nuclei of cranial nerves or in the anterior gray horns of the spinal cord b. basal ganglia neurons assist movement by providing input via the thalamus to UMNs c. cerebellar neurons also assist movement by providing input via the thalamus to UMNs e. axons of most UMNs synapse with interneurons which in turn synapse with lower motor neurons (LMNs) whose axons innervate skeletal muscles; since each LMN receives and integrates excitatory and inhibitory input from many presynaptic neurons (e.g., UMNs and interneurons), LMNs are also called the final common pathway iii. the direct motor pathways convey impulses that result in precise, voluntary movements via three pairs of tracts containing axons of UMNs: a. lateral corticospinal tracts: - most of the axons of UMNs decussate in the medulla to form the lateral corticospinal tracts in the right and left lateral white columns of the spinal cord - axons of LMNs exit all levels of the spinal cord to innervate skeletal muscles in the limbs, hands, and feet b. anterior corticospinal tracts: - some of the axons of UMNs do not cross over in the medulla but descend on the same side to form the anterior corticospinal tracts in the right and left anterior white columns c. corticobulbar tracts: - some axons of UMNs extend to the midbrain where they form the corticobulbar tracts in right and left cerebral peduncles - the axons terminate in nuclei of nine pairs of cranial nerves; LMNs of these cranial nerves convey nerve impulses that control precise, voluntary movements of the eyes, tongue, neck, chewing, facial expression, and speech

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4. Indirect motor pathways: (see Table 21.4) i. Indirect (or extrapyramidal) pathways include all somatic motor tracts other than the corticospinal and corticobulbar tracts.

ii. Indirect (extrapyramidal) motor output from the brain arises from various nuclei in the brain stem and travels along five major pairs of spinal cord tracts (and terminate on interneurons and LMNs):

Application to Health Spinal Cord Trauma: Paralysis Paralysis ­ loss of motor function Flaccid paralysis ­ severe damage to the ventral root or anterior horn cells Lower motor neurons are damaged and impulses do not reach muscles There is no voluntary or involuntary control of muscles Spastic paralysis ­ only upper motor neurons of the primary motor cortex are damaged Spinal neurons remain intact and muscles are stimulated irregularly There is no voluntary control of muscles Spinal Cord Trauma: Transection Cross sectioning of the spinal cord at any level results in total motor and sensory loss in regions inferior to the cut Paraplegia ­ transection between T1 and L1 Quadriplegia ­ transection in the cervical region Poliomyelitis Destruction of the anterior horn motor neurons by the poliovirus Early symptoms ­ fever, headache, muscle pain and weakness, and loss of somatic reflexes Vaccines are available and can prevent infection Amyotrophic Lateral Sclerosis (ALS) Lou Gehrig's disease ­ neuromuscular condition involving destruction of anterior horn motor neurons and fibers of the pyramidal tract Symptoms ­ loss of the ability to speak, swallow, and breathe Death occurs within five years Linked to malfunctioning genes for glutamate transporter and/or superoxide dismutase

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LABORATORY IDENTIFICATION Neuron Model: Cell body (Soma) Nucleus Nissl bodies (Nissl Granules) neurofibril Dendrites; Synaptic end bulbs from other neurons Axon hillock Axon Schwann cell: Myelin sheath, nucleus of Schwann cell Node of Ranvier Microscope slide Spinal cord or Cerebrum or Medulla Oblongata: A neuron with soma, nucleus, and a process Glial cells Nerve (from the slide of artery, vein, and nerve) Fascicle Perineurium Epineurium

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MUSCULAR TISSUE

CHAPTER 10

Introduction 1. Bones provide leverage and form the framework of the body, but motion results from alternating contraction (shortening) and relaxation of muscles. 2. Muscular tissue also stabilizes the body's position, regulates organ volume, generates heat, and propels fluids and food through various body systems. 3. The study of muscles is called myology. Overview of Muscle Tissue 1. There are three types of muscle tissue (see Table 10.2): i. Skeletal muscle tissue a. moves bones (and, in some cases, skin or other soft tissues) b. striated c. primarily voluntary ii. Cardiac muscle tissue a. forms most of the wall of the heart b. striated c. involuntary d. some cells have autorhythmicity e. regulated by autonomic nervous system and certain hormones iii. Smooth muscle tissue a. located in the walls of hollow internal structures (and arrector pili muscles) b. nonstriated, i.e., smooth c. involuntary d. some cells have autorhythmicity e. regulated by autonomic nervous system and certain hormones Skeletal and smooth muscle cells are elongated and are called muscle fibers Muscle contraction depends on two kinds of myofilaments ­ actin and myosin Sarcolemma ­ muscle plasma membrane Sarcoplasm ­ cytoplasm of a muscle cell Prefixes ­ myo, mys, and sarco all refer to muscle Functions of muscular tissue: Producing body movement Stabilizing body position Storing and moving substances within the body Producing heat Properties of Muscular Tissue Excitability, or irritability ­ the ability to receive and respond to stimuli Contractility ­ the ability to shorten forcibly Extensibility ­ the ability to be stretched or extended Elasticity ­ the ability to recoil and resume the original resting length Skeletal Muscle Tissue 1. Each muscle consists of numerous muscle fibers.

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2. Typically, a muscle belly (body) is attached to bones by tendons: - a tendon is a cord of dense connective tissue that attaches a muscle to the periosteum of a bone - some tendons are aponeuroses - an aponeurosis is a broad, flat sheet of connective tissue that attaches a muscle to the periosteum of a bone, another muscle, or the skin 3. Three layers of connective tissue extend from the muscle belly and become continuous with the tendon: i. endomysium surrounds individual muscle fibers ii. perimysium surrounds fascicles (bundles of muscle fibers) iii. outer epimysium encircles the entire muscle belly 4. Various skeletal muscles are grouped together and protected by large connective tissue sheets called fascia. Microscopic Anatomy of a Skeletal Muscle Fiber Each fiber is a long, cylindrical cell with multiple nuclei just beneath the sarcolemma Fibers are 10 to 100 m in diameter, and up to hundreds of centimeters long Each cell is a syncytium produced by fusion of embryonic cells, myoblasts. Sarcoplasm has numerous glycosomes and a unique oxygen-binding protein called myoglobin Fibers contain the usual organelles, myofibrils, sarcoplasmic reticulum, and T tubules Sarcolemma: plasma membrane. T (transverse) tubules: are continuous with the sarcolemma They conduct impulses to the deepest regions of the muscle These impulses signal for the release of Ca2+ from adjacent terminal cisternae. Sarcoplasm: cell plasma, containing myoglobin (red, only in muscle fibers, O2-binding proteins). Sarcoplasmic reticulum (SR): SR is an elaborate, smooth endoplasmic reticulum that surrounds each myofibril Paired terminal cisternae form perpendicular cross channels; stores Ca2+ in a relaxed muscle fiber, releases Ca2+ triggers muscle contraction. Triad: A T tubule and the two terminal cisterns of the SR on either side of it form a triad. Myofibrils Myofibrils are densely packed, rodlike contractile elements They make up most of the muscle volume The arrangement of myofibrils within a fiber is such that a perfectly aligned repeating series of dark A bands and light I bands is evident Filaments and the Sarcomere: Within myofibrils are even smaller structures called filaments; are of two types ­ thick and thin Thick filaments: are composed of the protein myosin Each myosin molecule has a rodlike tail and two globular heads Thin filaments: are chiefly composed of the protein actin The subunits contain the active sites to which myosin heads attach during contraction Tropomyosin and troponin are regulatory subunits bound to actin. A band: dark band, entire length of thick filament, part of thin filament I band: light band, contains thin filament only

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H zone: in the center of each A band, contains thick but not thin filaments M line: center of H zone Z-disc ­ coin-shaped sheet of proteins (connectins) that anchors the thin filaments and connects myofibrils to one another Sarcomere: The smallest contractile unit of a muscle The region of a myofibril between two successive Z discs Filaments - myofibrils muscle fibers fascicles a muscle Neuromuscular Junction Axon terminal of the motor neuron, which divides into a cluster of synaptic end bulb Synaptic vesicles in each bulb contain the neurotransmitter acetylcholine (ACh) The motor end plate of a muscle, which is a specific part of the sarcolemma that contains ACh receptors Synaptic cleft Motor Unit: The Nerve-Muscle Functional Unit A motor unit is a motor neuron and all the muscle fibers it supplies The number of muscle fibers per motor unit can vary from four to several hundred Muscles that control fine movements (fingers, eyes) have small motor units Large weight-bearing muscles (thighs, hips) have large motor units Contraction and Relaxation of Skeletal Muscle Fibers Excitation and Contraction of Muscle 1. An action potential (nerve impulse) reaches the synaptic end bulbs of a motor neuron. 2. Triggers exocytosis of the synaptic vesicles. 3. Released ACh diffuses across the synaptic cleft. 4. ACh binds to ACh receptors, allow inflow of Na+, initiating a muscle action potential. 5. The muscle action potential propagates along the sarcolemma through the T tubule system and to the SR. 6. Triggers Ca2+ release from terminal cisternae. Sliding filament mechanism: In the presence of Ca2+ and ATP, the skeletal muscle shortens because the thick and thin filaments slide past each other: 7. Ca2+ binds to troponin and causes: The blocking action of tropomyosin to cease Actin active binding sites to be exposed 8. Myosin heads attach to the thin filaments at both ends of a sarcomere, and pulling thin filaments toward the M line. 9. As thin filaments slide inward and meet at the center of a sarcomere, the Z discs come close together, sarcomere shortens. 10. Hydrolysis of ATP powers this cycling process 11. Ca2+ is removed into the SR, tropomyosin blockage is restored, and the muscle fiber relaxes There are 2 major types of contraction: i. in an isotonic contraction, tension remains almost constant while the muscle changes its length; there are two subtypes:

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a) in a concentric isotonic contraction, the tension overcomes the resistance and the muscle shortens b) in an eccentric isotonic contraction, tension slows the lengthening of the muscle so that the muscle lengthens as it contracts ii. in an isometric contraction, a muscle develops tension but does not shorten because the tension is not great enough to exceed the resistance Types of Skeletal Muscle Fibers 1. Skeletal muscle fibers are not all identical in structure or function: i. Muscle fibers that have a high content of myoglobin, a red oxygen-storing protein (as well as more mitochondria and a rich blood supply), are called red muscle fibers. ii. Muscle fibers that have a low content of myoglobin are called white muscle fibers. iii. Based on structural and functional characteristics, skeletal muscle fibers are classified into three types (see Table 10.1): a. slow oxidative (SO) fibers or type I fibers b. fast oxidative-glycolytic (FOG) fibers or type IIa fibers c. fast glycolytic (FG) fibers or type IIb fibers iv. Most skeletal muscles contain a mixture of all three types of skeletal muscle fibers, but their proportion varies depending on the usual action of the muscle; however, the muscle fibers in any one motor unit are all of the same type. 2. The total number of skeletal muscle fibers and the relative percentages of fast and slow fibers in each muscle do not change significantly after birth, but the characteristics of the muscle fibers present may be somewhat altered in various ways by various types of exercise. Hypertrophy: enlargement of existing muscle fibers. Hyperplasia: an increase in the number of fibers.

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THE MUSCULAR SYSTEM CHAPTER 11 p.311 Origin: the attachment of a muscle's tendon to the stationary bone. Insertion: the attachment of a muscle's tendon to the movable bone. Lever Systems Lever ­ a rigid bar that moves on a fulcrum, or fixed point Effort ­ force applied to a lever Load ­ resistance moved by the effort First class ­ the fulcrum is between the load and the efforts Examples: scissors, the head resting on the vertebral column Second class ­ the load is between the fulcrum and the effort Examples: wheelbarrow, standing up on your toes Third class ­ the effort is applied between the fulcrum and the load Example: a pair of forceps; the most common levels in the body: elbow joint (F), biceps brachii (E), the weight of the hand and forearm is (L). Coordination within Muscle Groups Skeletal muscles work together or in opposition Muscles only pull (never push) As muscles shorten, the insertion generally moves toward the origin Whatever a muscle (or group of muscles) does, another muscle (or group) undoes Muscle Classification: Functional Groups Prime movers ­ provide the major force for producing a specific movement Antagonists ­ oppose or reverse a particular movement Synergists- add force to a movement; Reduce undesirable or unnecessary movement Fixators ­ synergists that immobilize a bone or muscle's origin Naming Skeletal Muscles Location of muscle ­ bone or body region associated with the muscle Shape of muscle ­ e.g., the deltoid muscle (deltoid = triangle) Relative size ­ e.g., maximus (largest), minimus (smallest), longus (long) Direction of fibers ­ e.g., rectus (fibers run straight), transversus, and oblique (fibers run at angles to an imaginary defined axis) Number of origins ­ e.g., biceps (two origins) and triceps (three origins) Location of attachments ­ named according to point of origin or insertion Action ­ e.g., flexor or extensor Arrangement of Fascicles Parallel ­ fascicles run parallel to the long axis of the muscle (e.g., sartorius) Fusiform ­ spindle-shaped muscles (e.g., biceps brachii) Pennate ­ short fascicles that attach obliquely to a central tendon running the length of the muscle (e.g., rectus femoris) Convergent ­ fascicles converge from a broad origin to a single tendon insertion (e.g., pectoralis major) Circular ­ fascicles are arranged in concentric rings (e.g., orbicularis oris)

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LABORATORY IDENTIFICATION Skeletal muscle fiber (cell) model: Endomysium Sarcolemma Nucleus Myofibrils A band and I band Z disc and sarcomere Motor end plate Axon Myelin sheath (Schwann cell) Axon terminal Synaptic end bulb Sarcoplasmic reticulum and Triad model: Endomysium, Sarcolemma Myofibrils A band and I band, Nucleus Sarcoplasmic reticulum Triad: Transverse tubules Terminal cisterns Motor end plate, Axon Myelin sheath Synaptic end bulb Microscope slides: Skeletal muscle tissue: Longitudinal section: Muscle fibers (cells), nucleus, (A and I bands, observation only) Cross section: Muscle fibers, nucleus, fascicles, and perimysium Cardiac muscle: muscle fibers, nucleus, intercalated disc

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THE CARDIOVASCULAR SYSTEM: THE HEART

CHAPTER 14

A. Introduction p. 453 1. The heart is the pump of the cardiovascular system; its function is to propel blood through the estimated 100,000 km of blood vessels. 2. Cardiology is the study of the normal heart and diseases associated with it. B. Location and Surface Projection of the Heart 1. The heart is a hollow, cone-shaped organ that is about the size of a person's closed fist. 2. The heart is about 12 cm long, 9 cm wide, and 6 cm thick. 3. It is located between the lungs in the mediastinum, which is mass of tissue that extends from the sternum to the vertebral column and between the pleurae of the lungs, including heart, esophagus, trachea, thymus, and large blood vessels 4. About two thirds of the heart's mass lies to the left of the body's midline. 5. The apex is the lower, pointed end to the left, 5th intercostal space; and the base is the broader, upper portion. 6. The heart has an anterior surface and an inferior surface; the right border faces the right lung and the left border faces the left lung. 7. Surface projection refers to outlining the shape of an organ on the surface of the body; the heart can be projected to the anterior surface of the chest by locating the following landmarks: i. superior right point ii. superior left point iii. inferior left point iv. inferior right point C. Pericardium 1. The pericardium is a sac that surrounds and protects the heart. 2. The pericardium consists of two major layers: i. outer fibrous pericardium which prevents overstretching of the heart, provides protection, and anchors the heart in the mediastinum. ii. deeper serous pericardium, which itself consists of two sublayers: a. outer parietal layer, which is fused to the fibrous pericardium b. inner visceral layer or epicardium - between these two sublayers is the pericardial cavity that contains pericardial fluid, a lubricating fluid that reduces friction between the layers as the heart moves. D. Layers of the Heart Wall 1. The wall of the heart consists of three layers: i. outer epicardium composed of mesothelium and connective tissue ii. thick, middle myocardium composed of cardiac muscle tissue iii. inner endocardium composed of connective tissue covered by endothelium that is continuous with the endothelium of the blood vessels. E. Chambers of the Heart

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1. The two superior chambers are the right and left atria, each having an anterior appendage called an auricle that allows an atrium to hold a larger volume of blood. 2. The two inferior chambers are the right and left ventricles. 3. The pulmonary pump, consisting of the right atrium and right ventricle, pumps deoxygenated blood toward the lungs; the systemic pump, consisting of the left atrium and left ventricle, pumps oxygenated blood toward the rest of the body. 4. The surface of the heart has three major grooves: i. coronary sulcus ii. anterior interventricular sulcus iii. posterior interventricular sulcus Right Atrium: 5. The right atrium receives deoxygenated blood from three veins: i. superior vena cava (SVC) brings blood from most parts of the body superior to the heart ii. inferior vena cava (IVC) brings blood from all parts of the body inferior to the diaphragm iii. coronary sinus receives blood from most of the vessels draining the wall of the heart 6. The anterior right atrial wall has internal muscular ridges called pectinate muscles. 7. The interior of the heart has an interatrial septum that separates the atria; this septum has an oval depression called the fossa ovalis. 8. Blood in the right atrium flows into the right ventricle through the tricuspid valve (or right atrioventricular valve).

Right ventricle: 9. The inner surface of the right ventricle has an irregular surface of ridges called trabeculae carneae; chordae tendineae and their associated papillary muscles ensure that the cusps of the tricuspid valve permit blood to flow into the right ventricle but prevent backflow of blood into the right atrium. 10. The interventricular septum separates the two ventricles. 11. The right ventricle pumps blood through the pulmonary valve into the pulmonary trunk which divides into the right and left pulmonary arteries. Left Atrium: 12. Oxygenated blood returns from the lungs via four pulmonary veins that empty into the left atrium; there are two pulmonary veins (one superior and one inferior) draining blood from each lung. 13. Blood in the left atrium flows into the left ventricle through the bicuspid (mitral) valve (or left atrioventricular valve). Left Ventricle: 14. The left ventricle forms the apex of the heart. 15. The inner surface of the left ventricle has an irregular surface of ridges called trabeculae carneae; chordae tendineae and their associated papillary muscles

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ensure that the cusps of the bicuspid valve permit blood to flow into the left ventricle but prevent backflow of blood into the left atrium. 16. The left ventricle pumps blood through the aortic valve into the ascending aorta. 17. The ascending aorta gives rise to the right and left coronary arteries which deliver blood to the walls of the heart. 18. The ascending aorta is continuous with the arch of the aorta, which is followed by the descending aorta (which consists of the thoracic aorta and the abdominal aorta). 19. Branches of the aorta deliver blood throughout the systemic circulation. 20. During fetal life the temporary ductus arteriosus shunts blood from the pulmonary trunk into the aorta; shortly after birth this blood vessel normally closes, leaving a remnant called the ligamentum arteriosum. Myocardial Thickness: 21. The walls of the atria are relatively thin whereas the walls of the ventricles are relatively thick; the wall of the left ventricle is much thicker than that of the right ventricle. F. Fibrous Skeleton of the Heart 1. The heart wall contains dense connective tissue that forms the fibrous skeleton of the heart which consists primarily of four fibrous rings (that surround the four heart valves): a. right atrioventricular fibrous ring b. left atrioventricular fibrous ring c. pulmonary fibrous ring d. aortic fibrous ring G. Heart Valves 1. Four valves prevent backflow of blood in the heart and are composed of dense connective tissue covered by endocardium. 2. There are two atrioventricular (AV) valves: i. tricuspid valve located between the right atrium and the right ventricle ii. bicuspid (mitral) valve located between the left atrium and the left ventricle 3. Chordae tendineae and their associated papillary muscles ensure that the cusps of the AV valves permit blood to flow into the ventricles but prevent backflow of blood into the atria. 4. There are two semilunar (SL) valves (each consisting of three semilunar cusps): i. pulmonary valve located between the pulmonary trunk and the right ventricle ii. aortic valve located between the aorta and the left ventricle 5. The cusps of the semilunar valves permit ejection of blood from the ventricles but prevent backflow of blood into the heart. H. Circulation of Blood 1. The heart pumps blood into two closed circuits: i. systemic circulation ii. pulmonary circulation

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2. The left side of the heart is the pump for the systemic circulation; it receives oxygenated blood from the lungs and then pumps this blood into the aorta which subsequently branches into systemic arteries that carry this blood to all organs except the lungs' alveoli. 3. In tissues, arteries branch into arterioles and subsequently into systemic capillaries where nutrients, wastes, gases, etc. are exchanged between the blood and the surrounding cells. 4. Capillaries merge to deliver deoxygenated blood into systemic venules which subsequently merge to form systemic veins that carry this blood to the right atrium of the heart. 5. The right side of the heart is the pump for the pulmonary circulation; it receives deoxygenated blood returning from the systemic circulation and pumps it into the pulmonary trunk which subsequently branches into pulmonary arteries that carry this blood to the pulmonary capillaries where the blood becomes oxygenated. Coronary Circulation: 6. The flow of blood through the blood vessels that penetrate the myocardium is called the coronary (cardiac) circulation. 7. Right and left coronary arteries, which deliver oxygen and nutrients, are branches of the ascending aorta: i. the left coronary artery divides into: a. anterior interventricular branch or left anterior descending (LAD) artery b. circumflex branch ii. the right coronary artery divides into: a. posterior interventricular branch b. marginal branch 8. The myocardium contains many anastomoses that provide alternate routes, called collateral circuits, for blood to reach a particular tissue. 9. Blood draining out of the myocardium has collected carbon dioxide and wastes, and it flows into the coronary sinus whose principal tributaries are: i. great cardiac vein ii. middle cardiac vein iii. small cardiac vein iv. anterior cardiac vein I. The Cardiac Conduction System 1. During embryonic development about 1% of the cardiac muscle fibers become autorhythmic cells, allowing them to perform two major functions: i. act as a pacemaker to set the rhythm for contraction of the entire heart ii. form the conduction system to conduct action potentials throughout the myocardium; the components of the conduction system are: a. sinoatrial (SA) node which initiates each heartbeat and thus is the heart's natural pacemaker b. atrioventricular (AV) node c. atrioventricular (AV) bundle or bundle of His d. right and left bundle branches

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e. Purkinje fibers 2. The nervous system and various hormones may increase or decrease the pace of contractions (but the nervous system does not initiate contractions). 3. An electrocardiogram (ECG or EKG) is a recording of the heart's electrical activity; during each cardiac cycle a P wave, QRS wave and T wave are recorded. The route of action potentials through the conduction system: Sinoatrial (SA) node (in the right atrial wall, just inferior to the opening of the superior vena cava) atrioventricular node (AV) node (in the interatrial septum) atrioventricular (AV) bundle/ bundle of His right and left bundle branches Purkinjie fibers Congestive heart failure (CHF) is caused by: Coronary atherosclerosis Persistent high blood pressure Multiple myocardial infarcts Dilated cardiomyopathy (DCM)

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LABORATORY IDENTIFICATION Heart Models A. External Features: Apex (Base) Auricle - right and left Coronary sulcus, (anterior interventricular sulcus, posterior interventricular sulcus) Ligamentum arteriosum Ascending aorta Arch of aorta (Aortic arch) (ABCs) Brachiocephalic trunk Common carotid (left) artery Subclavian (left) artery B. Right Heart Pump: 1. Vessels - superior vena cava, inferior vena cava, pulmonary trunk, right and left pulmonary arteries 2. Right atrium - fossa ovalis, opening (orifice) of coronary sinus 3. Right ventricles - chordae tendineae, papillary muscles, trabeculae carneae 4. Interventricular septum 5. Valves ­ tricuspid (right atrioventricular) valve, pulmonary (semilunar) valve C. Left Heart Pump: 1. Vessels ­ right pulmonary veins, left pulmonary veins 2. Right atrium 3. Right ventricle - chordae tendineae, papillary muscles, trabeculae carneae 4. Valves - bicuspid (mitral, left atrioventricular) valve, aortic (semilunar) valve D. Coronary Circulation: Right coronary artery: Marginal branch, posterior interventricular branch Left coronary artery: Circumflex branch, anterior interventricular branch E. Drainage: great cardiac vein, middle cardiac vein, coronary sinus

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THE CARDIOVASCULAR SYSTEM: BLOOD VESSELS

CHAPTER 15

A. Anatomy of Blood Vessels p.481 1. Blood vessels are tubes that carry blood away from the heart toward the tissues of the body and then return the blood to the heart. 2. Arteries carry blood away from the heart. 3. Arteries branch extensively and eventually give rise to arterioles. 4. Arterioles branch into capillaries; substances are exchanged between the blood and surrounding tissues through the walls of capillaries. 5. Capillaries merge to form venules. 6. Venules merge to form veins. 7. Veins merge with each other to form progressively larger veins which carry the blood back to the heart. 8. Larger blood vessels are served by their own blood vessels called vasa vasorum, located within their walls. 9. Angiogenesis refers to the growth of new blood vessels. B. Basic Structure of a Blood Vessel 1. Blood flows through the lumen of blood vessels. 2. The walls of blood vessels consist of three major layers: i. inner tunica interna (intima) which consists of: a. endothelium b. basement membrane c. internal elastic lamina ii. middle (thickest) tunica media which consists of: a. elastic fibers which provide compliance (i.e., distensibility) b. smooth muscle fibers iii. outer tunica externa which consists of: a. primarily elastic and collagen fibers b. a less prominent external elastic lamina that contains the vasa vasorum in larger blood vessels C. Arteries 1. Vasoconstriction occurs when vascular smooth muscle tissue contracts to decrease the diameter of the lumen. 2. Vasodilation occurs when vascular smooth muscle tissue relaxes to increase the diameter of the lumen. 3. There are two major sets of arteries: i. large elastic (conducting) arteries whose elastic fibers, organized to form the elastic lamellae, recoil during relaxation of the heart to force blood to flow onward; these blood vessels act as pressure reservoirs ii. medium-sized muscular (distributing) arteries whose smooth muscle tissue is capable of greater vasoconstriction and vasodilation to regulate the rate of blood flow to target tissues; vascular tone stiffens the vessel wall D. Arterioles

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1. An arteriole is a very small branch of an artery that delivers blood to a capillary. 2. Through vasoconstriction and vasodilation arterioles play major roles in: i. regulating blood flow from arteries to capillaries ii. regulating blood pressure 3. Arterioles are therefore known as resistance vessels. 4. The terminal end of an arteriole is a region called the metarteriole; at its junction with a capillary is a precapillary sphincter. E. Capillaries 1. A capillary is a microscopic blood vessel that usually connects an arteriole to a venule; the flow of blood from arterioles to venules through capillaries is called the microcirculation. 2. Capillaries are called exchange vessels because the primary function of capillaries is to permit the exchange of nutrients and wastes between the blood and surrounding tissue cells; this occurs easily because the walls of capillaries consist of only two thin layers: i. endothelium ii. basement membrane

3. A metarteriole emerges from an arteriole and supplies a group of 10-100 capillaries that form a capillary bed; a thoroughfare channel is a capillary that connects an arteriole directly to a venule.

4. True capillaries emerge from arterioles or metarterioles and are not on the direct flow route from arteriole to venule; at their sites of origin, there is a ring of smooth muscle fibers called a precapillary sphincter that controls, via vasomotion, the flow of blood into a true capillary. 5. Many capillaries are continuous capillaries in which the plasma membranes of the endothelial cells form a continuous tube that is interrupted only by intercellular clefts. 6. Other capillaries are fenestrated capillaries in which there are fenestrations (pores) between the neighboring plasma membranes. 7. In some organs, there are sinusoids which are wider, more tortuous capillaries whose walls contain large pores and intercellular clefts; sinusoids may contain specialized lining cells (e.g., phagocytic cells in liver sinusoids). 8. A portal system delivers blood via a portal vein from one capillary network directly to another capillary network. F. Venules 1. Several capillaries unite to form small vessels called postcapillary venules which in turn unite to form muscular venules. 2. Venules deliver blood from capillaries to veins. G. Veins 1. Veins have relatively thin walls because the tunica interna and tunica media are thin layers. 2. Many veins, especially those in the limbs, have valves which: i. are composed of two or more thin folds of tunica interna that form flap-like cusps which project into the lumen. ii. function to prevent backflow of blood and aid in moving blood toward the heart

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3. A vascular (venous) sinus is a vein with a thin endothelial wall that has no smooth muscle to alter its diameter (e.g., coronary sinus). 4. Superficial veins travel through the hypodermis; deep veins travel below the fascia between skeletal muscles. H. Anastomoses 1. The union of branches of two or more arteries supplying the same body region is called an anastomosis; anastomoses provide alternative routes, i.e., collateral circulation, for blood to reach a target tissue or organ (anastomoses may also occur between veins and between arterioles and venules). 2. Arteries that do not anastomose are called end arteries; occlusion of an end artery interrupts the blood supply to the target tissue and may result in necrosis of that tissue. I. Blood Distribution 1. Systemic veins and venules contain, at rest, about 64% of the blood volume and are therefore called blood reservoirs. 2. When more blood is needed elsewhere, vasoconstriction reduces the volume of blood in venous reservoirs in order to provide a greater volume to active tissues (e.g., active skeletal muscles). 3. Vasoconstriction of veins, called venoconstriction, also helps to compensate for blood pressure decrease during hemorrhage. 4. The major blood reservoirs are the veins of the abdominal organs (especially the liver and spleen) and the skin. J. Circulatory Routes 1. Blood vessels are organized into parallel circulatory routes that deliver blood throughout the body. 2. The circulatory routes are: i. systemic circulation, which includes all blood vessels carrying blood from the left ventricle, through body organs, and back to the right atrium; its subdivisions include: a. coronary (cardiac) circulation b. cerebral circulation c. hepatic portal circulation

ii. pulmonary circulation, which includes all blood vessels carrying blood from the right ventricle, through the lungs, and back to the left atrium

iii. fetal circulation exists only in the fetus and consists of structures that permit exchange of substances between the developing fetus and its mother. 3. Systemic Circulation: i. The systemic circulation delivers oxygen and nutrients to tissues and removes carbon dioxide and other wastes and heat from the tissues of the body. ii. All systemic arteries branch from the aorta which consists of the following segments: a. ascending aorta b. arch of the aorta c. thoracic aorta d. abdominal aorta

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iii. All systemic veins deliver blood to (all of which empty into the right atrium): a. superior vena cava b. inferior vena cava c. coronary sinus The Fetal Circulation p.533 The lungs and GI organs do not begin to function until birth. The exchange of materials between fetal and maternal circulation occurs through the placenta. Scheme of fetal circulation - Blood passes from the fetus to the placenta via two umbilical arteries (deoxygenated blood) - The oxygenated blood returns from the placenta via a single umbilical vein - Some blood enter liver; some into ductus venosus inferior vena cava right atrium - From the right atrium, most of the blood via foramen ovale to left atrium (bypass the lung), little goes to pulmonary trunk - From the pulmonary trunk, most blood via ductus arteriosus to aorta (bypass the lung), little of the blood lungs left atrium aorta systems. Prenatal: Umbilical vein (1) becomes Umbilical arteries (2) Ductus venosus Foramen ovale Ductus arteriosus Postnatal Ligamentum teres Medial umbilical ligaments Ligamentum venosum Fossa ovalis Ligamentum arteriosum

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The Lymphatic System and Immunity

Chapter 16

p.541

A. Introduction 1. Most people remain healthy despite exposure to pathogens, UV rays, toxins, cuts, etc. 2. Immunity or resistance is the ability to ward off damage or disease through our defenses; lack of resistance is termed susceptibility. 3. The two general types of immunity are: i. nonspecific (nonspecific) immunity ii. adaptive (specific) immunity 4. The lymphatic system consists of: i. a fluid called lymph ii. lymphatic vessels iii. several structures and organs that contain lymphatic tissue iv. red bone marrow (the site of lymphocyte production) 5. Lymph is interstitial fluid that has entered and flows through lymphatic vessels. 6. Lymphatic tissue is a specialized form of reticular connective tissue that contains large numbers of lymphocytes (the two major types being T cells and B cells). B. Functions of the Lymphatic System The lymphatic system has the following major functions: i. drains excess interstitial fluid ii. transports dietary lipids iii. carries out immune responses against specific microbes and abnormal cells C. Lymphatic Vessels and Lymph Circulation 1. Lymphatic capillaries are dead-end lymphatic vessels located in spaces between cells. 2. Lymphatic capillaries merge to form larger lymphatic vessels. 3. Lymphatic vessels resemble veins but have thinner walls and more valves. 4. Along the length of lymphatic vessels are lymph nodes which contain B cells and T cells. 5. Lymphatic vessels travel close to veins in the skin's subcutaneous tissue; in the viscera, they travel close to arteries, forming plexuses (networks) around them. 6. Lymphatic capillaries: i. are located throughout the body except in: a. avascular tissues b. central nervous system c. portions of the spleen d. red bone marrow ii. have a slightly larger diameter than blood capillaries iii. are called lacteals when located in villi; lacteals transport lipid-rich lymph called chyle from the small intestine into lymphatic vessels and ultimately into the blood 7. Lymph Trunks and Ducts: i. The lymphatic vessels that exit the most proximal group of each chain of lymph nodes merge to form lymph trunks; ii. These trunks deliver their lymph into the thoracic duct and the right lymphatic duct.

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iii. Thoracic (left lymphatic) duct: a. is about 38 - 45 cm long and begins at its lower end as a dilation called the cisterna chyli anterior to the second lumbar vertebra b. is the main collecting duct of the lymphatic system c. receives lymph from the left side of the head, neck, and chest, the left upper limb, and the entire body below the ribs d. the cisterna chyli receives lymph from the right and left lumbar trunks and the intestinal trunk e. the thoracic duct delivers lymph to the junction of the left internal jugular and subclavian veins iv. Right lymphatic duct: a. is about 1.2 cm long

b. drains lymph from the upper right side of the body

c. the right lymphatic duct delivers lymph to the junction of the right internal jugular and subclavian veins 8. Formation and Flow of Lymph: i. More fluid is filtered out of blood capillaries than is reabsorbed by them. ii. Each day, about 3 liters of this interstitial fluid drains into lymphatic capillaries. iii. This lymph flows through lymphatic vessels and eventually into the blood of the subclavian veins. iv. One major function of lymphatic vessels is to return fluid and any leaked plasma proteins to the blood. D. Lymphatic Organs and Tissues 1. Lymphatic organs and tissues are classified into two groups: i. primary lymphatic organs are the sites where stem cells divide and become immunocompetent; these organs include red bone marrow and the thymus, structures where B and T lymphocytes are produced ii. secondary lymphatic organs and tissues are the lymph nodes, spleen and lymphatic nodules; these are the sites where most immune responses occur Lymph Nodes Lymph nodes are the principal lymphoid organs of the body Nodes are imbedded in connective tissue and clustered along lymphatic vessels Aggregations of these nodes occur near the body surface in inguinal, axillary, and cervical regions of the body Their two basic functions are: Filtration ­ macrophages destroy microorganisms and debris Immune system activation ­ monitor for antigens and mount an attack against them Other Lymphoid Organs The spleen, thymus gland, and tonsils Peyer's patches and bits of lymphatic tissue scattered in connective tissue All are composed of reticular connective tissue and all help protect the body Only lymph nodes filter lymph Spleen Largest lymphoid organ, located on the left side of the abdominal cavity beneath the diaphragm

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It extends to curl around the anterior aspect of the stomach It is served by the splenic artery and vein, which enter and exit at the hilus Functions Site of lymphocyte proliferation Immune surveillance and response Cleanses the blood Additional Spleen Functions Stores breakdown products of RBCs for later reuse Spleen macrophages salvage and store iron for later use by bone marrow Site of fetal erythrocyte production (normally ceases after birth) Stores blood platelets Thymus A bilobed organ that secrets hormones (thymosin and thymopoietin) that cause T lymphocytes to become immunocompetent The size of the thymus varies with age It increases in size and is most active during childhood It stops growing during adolescence and then gradually atrophies The thymus differs from other lymphoid organs in important ways It functions strictly in T lymphocyte maturation It does not directly fight antigens Tonsils Simplest lymphoid organs; form a ring of lymphatic tissue around the pharynx Location of the tonsils Palatine tonsils ­ either side of the posterior end of the oral cavity Lingual tonsils ­ lie at the base of the tongue Pharyngeal tonsil ­ posterior wall of the nasopharynx Aggregates of Lymphoid Nodules Peyer's patches ­ isolated clusters of lymphoid tissue, similar to tonsils Found in the wall of the distal portion of the small intestine Similar structures are found in the appendix Peyer's patches and the appendix: Destroy bacteria, preventing them from breaching the intestinal wall Generate memory lymphocytes for long-term immunity MALT MALT ­ mucosa-associated lymphatic tissue is composed of: Peyer's patches, tonsils, and the appendix (digestive tract) Lymphoid nodules in the walls of the bronchi (respiratory tract) MALT protects the digestive and respiratory systems from foreign matter

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LABORATORY IDENTIFICATION On Circulatory Plaque Model: Arteries: Arch of aorta (Aortic arch) (ABCs) 1. Brachiocephalic trunk Right common carotid artery Right subclavian artery 2. Common carotid (left) artery 3. Subclavian (left) artery Veins: Internal jugular vein (right and left) Subclavian vein (right and left) Brachiocephalic vein (right and left) Superior vena cava Microscope slides (on Artery, vein, and nerve slide): Arteries: Internal elastic lamina Tunica media External elastic lamina Tunica externa Veins: Tunica media Tunica externa Lymphatic System: (on Torso model): Cisterna chili Thoracic duct

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BACK REGION Vertebral Column chapter 7, p.193 1. The vertebral column (spine or backbone or spinal column) is a strong, flexible rod that: i. surrounds and protects the spinal cord ii. supports the head iii. serves as a site of attachment for ribs and back muscles. 2. It is formed, in the adult, by 26 vertebrae: i. 7 cervical vertebrae ii. 12 thoracic vertebrae iii. 5 lumbar vertebrae iv. one sacrum formed by fusion of 5 sacral vertebrae v. one coccyx formed by fusion of (usually) 4 coccygeal vertebrae 3. The vertebral column has four alternating normal curves: i. anteriorly convex cervical curve ii. anteriorly concave thoracic curve iii. anteriorly convex lumbar curve iv. anteriorly concave sacral curve At birth, there is only a single anteriorly concave curve; the cervical and lumbar (i.e., secondary) curves develop in the early months of infancy as the child begins to hold its head erect and as the child begins to sit and walk, respectively. The four curves function to: a. increase the strength of the spine b. help maintain balance in the upright position c. absorb shocks from walking and jumping d. help protect the spine from fracture. Abnormal spine curvatures include scoliosis (abnormal lateral curve), kyphosis (hunchback), and lordosis (swayback) 4. Intervertebral discs are located between neighboring vertebrae (from C2 down to the sacrum): i. each consists of an outer annulus fibrosus and an inner nucleus pulposus ii. they form strong joints, permit various movements of the spine, and absorb vertical shock herniated (slipped) disc: the rupture of surrounding annulus fibrosus, the nucleus pulposus may herniated (protrude) posteriorly or into one of the adjacent vertebral bodies radiated pain. Vertebral Column: Ligaments Anterior and posterior longitudinal ligaments ­ continuous bands down the front and back of the spine from the neck to the sacrum; anterior: prevent hyperextension. Short ligaments connect adjoining vertebrae together 5. A typical vertebra has the following structural features: i. body ii. vertebral arch, which consists of:

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a. two pedicles (with vertebral notches) b. two laminae iii. 7 processes: a. two transverse processes b. one spinous process (spine) c. two superior articular processes with facets d. two inferior articular processes with facets As a consequence of the above structural features, each vertebra has a vertebral foramen (all the vertebral foramina in the spine are aligned to form the vertebral [spinal] canal) and there are intervertebral foramina located between all neighboring vertebrae on the right and left sides of the spine. 6. There are unique structural features in each of the vertebrae in the cervical, thoracic, and lumbar regions of the spine (see Table 7.5): - cervical vertebrae (C1 - C7): - transverse foramen - bifid spinous process (C2 - C6) - atlas - anterior and posterior arches - lateral masses - axis - dens or odontoid process - vertebra prominens - thoracic vertebrae (T1 - T12) - costal facets - facets and demifacets - lumbar vertebrae (L1 - L5) 7. Important surface markings of the sacrum include: a. anterior sacral foramina c. sacral ala d. median sacral crest e. lateral sacral crest f. posterior sacral foramina g. sacral canal h. sacral hiatus i. apex and base j. sacral cornua k. sacral promontory 8. coccyx Muscles: p.382 Erector Spinae: - The largest muscle mass of the back, consists of three groups: - Lateral: Iliocostalis; intermediate: Longissimus; medial: Spinalis - Chief extensor of the vertebral column - Also in controlling flexion, lateral flexion, and rotation of the column

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Spinal Cord

chapter 18,

p.584

A. Spinal Cord Anatomy 1. Surrounding and protecting the delicate nervous tissue of the spinal cord (and, in a similar way, the brain) are: i. vertebral column, including: a. vertebrae b. vertebral ligaments ii. three spinal meninges (surrounding the brain and continuous with the spinal meninges are the cranial meninges), which include: a. outermost meninx is the dura mater - it is composed of dense, irregular connective tissue - it extends from the level of the foramen magnum to the second sacral vertebra where it is close-ended

- surrounding it is the epidural space filled with fat and connective tissue which provide additional protection to the spinal cord

-

b. middle meninx is the avascular arachnoid mater - it consists of connective tissue with a spider web-like arrangement of collagen fibers and some elastic fibers - surrounding it is the subdural space filled with interstitial fluid c. innermost meninx is the pia mater - it is attached to the surface of the spinal cord (and brain) - it is a layer of connective tissue that contains collagen fibers and some elastic fibers as well as many blood vessels that provide nutrients and oxygen to the spinal cord (and brain) - surrounding it is the subarachnoid space filled with cerebrospinal fluid Membranous extensions of the pia mater called denticulate ligaments suspend the spinal cord in the middle of its dural sheath to provide protection against sudden displacement that could result in shock. iii. cushion of cerebrospinal fluid (produced in the brain) Spinal tap (Lumbar puncture) (L3 & L4; L4 & L5) p.589 2. External Anatomy of the Spinal Cord: i. It is roughly cylindrical and extends from the medulla oblongata to the superior border of the second lumbar vertebra in an adult. ii. It has two enlargements which are sites where nerves supplying the limbs emerge: a. cervical enlargement extends from the fourth cervical to the first thoracic vertebra b. lumbar enlargement extends from the ninth to the twelfth thoracic vertebra iii. At its lower end, the spinal cord has a tapering, cone-shaped portion called the conus medullaris which ends at the level of the intervertebral disc between the first and second lumbar vertebrae in an adult. iv. An extension of the pia mater called the filum terminale extends inferiorly from the conus medullaris to attach the spinal cord to the coccyx.

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v. The roots of spinal nerves emerging from the lower part of the spinal cord travel inferiorly to form the cauda equina. 3. Internal Anatomy of the Spinal Cord: i. Two grooves divide the spinal cord into right and left sides: a. anterior median fissure is a deep, wide groove on the ventral side b. posterior median sulcus is a shallow, narrow groove on the dorsal side ii. The spinal cord contains a core of gray matter, shaped like a butterfly when viewed in cross section, that is surrounded by white matter: a. the gray matter consists primarily of cell bodies of neurons, neuroglia, unmyelinated axons, and dendrites of interneurons and motor neurons b. the white matter consists of bundles of myelinated axons of motor neurons, interneurons, and sensory neurons

iii. The gray commissure is a region of gray matter that connects the two wings of the butterfly.

iv. At the center of the gray commissure is the central canal which extends throughout the entire length of the spinal cord; it is continuous with the fourth ventricle of the brain. v. Anterior to the gray commissure is the anterior (ventral) white commissure which connects the white matter of the left and right sides of the spinal cord. vi. The gray matter contains sensory nuclei and motor nuclei; the gray matter on each side of the spinal cord is subdivided into regions called horns: a. anterior (ventral) gray horns contain cell bodies of somatic motor neurons and motor nuclei which provide nerve impulses for contraction of skeletal muscles b. posterior (dorsal) gray horns contain somatic and autonomic sensory nuclei c. lateral gray horns (which are present only in the thoracic, upper lumbar, and sacral segments of the spinal cord) contain cell bodies of autonomic motor neurons that regulate activities of involuntary effectors vii. The white matter is subdivided by the anterior and posterior gray horns into regions called columns: a. anterior (ventral) white columns b. posterior (dorsal) white columns c. lateral white columns viii. Each column contains bundles of nerve axons called tracts: a. sensory (ascending) tracts transmit nerve impulses upward to the brain b. motor (descending) tracts transmit nerve impulses downward from the brain Spinal cord tracts are continuous with tracts in the brain. ix. The various spinal cord segments vary in size, shape, relative amounts of gray and white matter, and distribution and shape of gray matter; these features are summarized in Table 18.1. C. Spinal Nerves 1. Spinal nerves and their branches are components of the PNS

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2.

3.

4.

5.

i. Each of the 31 pairs of spinal nerves emerge from a spinal segment; the spinal nerves are named and numbered according to the region and level of the spinal cord from which they emerge: a. 8 pairs of cervical nerves (the first pair emerge between the atlas and the occipital bone) represented as C1-C8 b. 12 pairs of thoracic nerves represented as T1-T12 c. 5 pairs of lumbar nerves represented as L1-L5 d. 5 pairs of sacral nerves represented as S1-S5 e. 1 pair of coccygeal nerves (represented as Co1) ii. Each spinal nerve arises from the spinal cord as a series of small rootlets which converge to form larger roots; each spinal nerve is formed by the merger of two roots: a. posterior or dorsal root contains sensory nerve fibers which transmit nerve impulses from the periphery into the spinal cord; it has an enlargement called the posterior or dorsal root ganglion which contains the cell bodies of these sensory neurons b. anterior or ventral root contains motor neuron axons which transmit nerve impulses from the spinal cord to effector organs and cells The merger of a posterior root and an anterior root (which occurs at an intervertebral foramen) results in every spinal nerve being a mixed nerve called a spinal nerve trunk. Shortly after passing through its intervertebral foramen, a spinal nerve divides into several branches called rami: i. posterior (dorsal) ramus serves the deep muscles and skin of the posterior surface of the trunk ii. anterior (ventral) ramus serves the muscles and structures of the limbs and the skin of the lateral and anterior surfaces of the trunk iii. meningeal branch reenters the vertebral canal via the intervertebral foramen and supplies the vertebrae, vertebral ligaments, blood vessels of the spinal cord, and the meninges iv. rami communicantes are components of the autonomic nervous system The anterior rami of spinal nerves, except for thoracic nerves T2-T12, form networks on both right and left sides of the body that are called plexuses; emerging from the plexuses are nerves that bear names which often describe the general regions they serve or the routes that they follow. The major pairs of plexuses (see Exhibits 18.1­18.4) are: i. cervical plexuses ii. brachial plexuses iii. lumbar plexuses

iv. sacral plexuses (two small coccygeal plexuses are also present)

6. The anterior rami of spinal nerves T2-T12 do not enter into the formation of plexuses and are called intercostal or thoracic nerves; these nerves travel directly to the intercostal regions and the nearby muscles and skin regions that they innervate. 7. Dermatomes: i. The skin over the entire body is supplied by somatic sensory neurons that carry nerve impulses into the spinal cord and brain stem.

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ii. The underlying skeletal muscles receive signals from somatic motor neurons that carry impulses out of the spinal cord. iii. Each spinal nerve supplies a specific, predictable segment of the body; the area of the skin that provides sensory input to one pair of spinal nerves or to cranial nerve V (for the face and scalp) is called a dermatome. iv. The nerve supply in adjacent dermatomes overlaps slightly or, in some cases, more extensively. 8. Every spinal nerve (and cranial nerve) is surrounded and protected by connective tissue coverings: i. each axon is wrapped in a layer called the endoneurium ii. groups of axons with their endoneuria are arranged in bundles called fasciculi, and each fasciculus is wrapped in a layer called the perineurium iii. groups of fasciculi collectively form a nerve which is covered by a layer called the epineurium B. Spinal Cord Functions 1. The spinal cord has two major functions in maintaining homeostasis: i. The white matter tracts in the white matter of the spinal cord transmit nerve impulses between the brain and the periphery.

ii. The gray matter of the spinal cord receives and integrates the incoming and outgoing information.

Reflex and Reflex Arc p.606 Five components of a reflex arc: 1. Sensory receptor: responds to a stimulus by producing a receptor potential. 2. Sensory neuron: axon conducts impulses from receptor to integrating center. 3. Integrating center: one or more regions of gray matter in CNS. 4. Motor neuron: axon conducts impulses from integrating center to effector. 5. Effector: muscle or gland. (Reflexes and Diagnosis - Patellar reflex (knee jerk): involves extension of the knee joint by contraction of the quadriceps femoris muscle in response to tapping the patellar ligament. - Achilles reflex (ankle jerk): this stretch reflex involves extension (planter flexion) of the foot by contraction of the gastrocnemius and soleus muscles in response to tapping the calcaneal (Achilles) tendon. - Babinski sign: results from gentle stroking of the lateral outer margin of the sole. The great toe extends, with or without fanning of the other toes. A positive Babinski sign after age 1 ½ is abnormal and indicates an interruption of the corticospinal tract.)

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LABORATORY IDENTIFICATION I. Surface Anatomy Vertebra prominens (C7) Spine of scapula (T3) Inferior Angle of scapula (T7) Iliac crest (L4) The triangle of auscultation: bounded by latissimus dorsi, trapezius and the vertebral border of the scapula II. Skeleton A. Vertebrae General features: Body Vertebral arch - pedicle, lamina Vertebral foramen Transverse process Spinous process Superior and inferior articular facet Intervertebral notch Specific features: distinguish between cervical, thoracic, and lumbar vertebrae. Cervical: Atlas (C1), axis (C2) and dens (odontoid process), bifid spinous process, transverse foramen, Thoracic (superior and inferior costal facets (for head of ribs), transverse costal facet (for tubercle of rib) Lumbar B. Ligaments Anterior longitudinal ligament (on Torso model) Ligamentum flavum (on spinal cord model) III. Musculature: Superficial: levator scapulae, trapezius, rhomboideus major & minor, latissimus dorsi Intermediate: serratus posterior inferior Deep: Erector spinae: iliocostalis, longissimus, and spinalis Neck: Splenius capitis; Semispinalis capitis IV. Nervous System Spinal cord A. Anterior median fissure, posterior median sulcus B. Gray matter: Anterior horn, posterior horn, gray commissure, central canal, *lateral horn C. White matter: Columns: anterior, posterior, lateral white column Roots: anterior root, posterior root, posterior root ganglion (spinal ganglion). Rami: anterior ramus, posterior ramus. D. Meninges: Epidural space, dura mater, arachnoid mater, subarachnoid space, pia mater

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E. Ligamentum flavum, *denticulate ligament F. Vessels: Internal vertebral venous plexus Vertebral artery *Anterior spinal artery (1) *Posterior spinal arteries (2) * Identify those structures on Denoyer-Geppert Spinal Cord model (Blue-colored) V. Sectional Anatomy A. Cross section through back region: Intervertebral disc, spinous process, transverse process,spinal cord Vertebral body and Cauda equina (not photographed) B. Sagittal section of cadaver (not photographed) Vertebra body, intervertebral disc, spinous process Dura mater, epidural space Spinal cord, cauda equine

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UPPER LIMB REGION SKELETAL SYSTEM Chapter 8 p.213 Appendicular Skeleton The appendicular skeleton is made up of the bones of the limbs and their girdles Pectoral girdles attach the upper limbs to the body trunk Pelvic girdle secures the lower limbs Pectoral Girdles (Shoulder Girdles) The pectoral girdles consist of the anterior clavicles and the posterior scapulae They attach the upper limbs to the axial skeleton in a manner that allows for maximum movement They provide attachment points for muscles that move the upper limbs Clavicles (Collarbones) The clavicles are slender, doubly curved long bones lying across the superior thorax The acromial (lateral) end articulates with the scapula, and the sternal (medial) end articulates with the sternum Scapulae (Shoulder Blades) The scapulae are triangular, flat bones lying on the dorsal surface of the rib cage, between the second and seventh ribs Scapulae have three borders and three angles Major markings include the scapular notch, the supraspinous and infraspinous fossae, the spine, the acromion, and the coracoid process The Upper Limb The upper limb consists of the arm (brachium), forearm (antebrachium), and hand (manus) Thirty-seven bones form the skeletal framework of each upper limb Arm The humerus is the sole bone of the arm It articulates with the scapula at the shoulder, and the radius and ulna at the elbow Major markings Proximal humerus includes the head, anatomical and surgical necks, greater and lesser tubercles, and the intertubercular groove Distal humerus includes the capitulum, trochlea, medial and lateral epicondyles, and the coronoid and olecranon fossae Medial portion includes the deltoid process Forearm The bones of the forearm are the radius and ulna They articulate proximally with the humerus and distally with the wrist bones They also articulate with each other proximally and distally at small radioulnar joints Interosseous membrane connects the two bones along their entire length Bones of the Forearm Ulna The ulna lies medially in the forearm and is slightly longer than the radius Forms the major portion of the elbow joint with the humerus Its major markings include the olecranon, coronoid process, trochlear notch, radial notch, and the styloid process

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Radius The radius lies opposite (lateral to) the ulna The superior surface of the head articulates with the capitulum of the humerus Medially, the head articulates with the radial notch of the ulna Major markings include the radial tuberosity, ulnar notch, and styloid process Hand Skeleton of the hand contains wrist bones (carpals), bones of the palm (metacarpals), and bones of the fingers (phalanges) Carpus (Wrist) Consists of eight bones Scaphoid, lunate, triquetral, and pisiform proximally Trapezium, trapezoid, capitate, and hamate distally Metacarpus (Palm) Five numbered (1-5) metacarpal bones radiate from the wrist to form the palm Their bases articulate with the carpals proximally, and with each other medially and laterally Heads articulate with the phalanges Phalanges (Fingers) Each hand contains 14 miniature long bones called phalanges Fingers (digits) are numbered 1-5, beginning with the thumb (pollex) Each finger (except the thumb) has three phalanges ­ distal, middle, and proximal The thumb has no middle phalanx Fractures: Falling on one's outstretched arm may result: one of the most frequently broken bones in the body: clavicle. Falling on an outstretched hand: a. Colle's fracture: fracture of the distal end of the radius. b. Carpal fracture: 70% involved scaphoid fracture. Carpal Tunnel (canal): The concave space formed by: Floor: 4 carpal bones: pisiform and hamate (ulnar side) and scaphoid and trapezium (radial side). Roof: flexor retinaculum (deep fascia) Contents: long flexor tendons of the digits & median nerve. Carpal tunnel syndrome: Excessive exercise, trauma, infection inflammation of the digital tendon sheaths compression of median nerve sensory changes over the lateral side of the hand & muscle weakness in the thenar eminence. Interosseous Membrane: between radius and ulna, separating anterior compartment of the forearm (flexors and pronators) from the posterior compartment (extensors and supinator). ARTICULATIONS Acromioclavicular joint: Shoulder (Glenohumeral) p.270 Ball-and-socket joint in which stability is sacrificed to obtain greater freedom of movement Head of humerus articulates with the glenoid fossa of the scapula

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Weak stability is maintained by: - Thin, loose joint capsule - Four ligaments ­ coracohumeral, and three glenohumeral - Tendon of the long head of biceps, which travels through the intertubercular groove and secures the humerus to the glenoid cavity - Rotator cuff: supraspinatus, infraspinatus, teres minor, subscapularis tendons of these muscles encircle the joint (except for the inferior portion) and blends with the articular capsule. - Glenoid labrum: rim of fibrocartilage, deepens and enlarges the glenoid cavity - Four bursae Movements: Dislocated shoulder: the most commonly dislocated joint; the head of the humerus becomes displaced inferiorly. Elbow Joint: p.273 a. Hinge: formed by the trochlear and capitulum of the humerus, the trochlear notch of the ulna, and the head of the radius. b. Capsule; ulnar and radial collateral ligaments c. Tennis elbow: pain at or near the lateral epicondyle of the humerus. Wrist (Radiocarpal) joint: a. Formed by: the distal end of the radius & lunate, scaphoid, and triquetrum. MUSCULAR SYSTEM Movements of Pectoral (Shoulder) Girdle Elevation Depression Abduction (protraction) Adduction (retraction) Upward rotation Downward rotation Ant. Thoracic Origin Insertion Coracoid process Action p.353

Pectoralis minor 2 ­5 or 3- 5 ribs Serratus anterior 1-8 or 1-9 ribs Post. Thoracic Trapezius Occipital bone, ligamentum nuchae, spines of C7-T12 Transverse processes of C1-4 Spines of T2-T5

Abducts scapula and rotates it downward Vertebral border & Abducts scapula and rotates it inf. angle of scapula upward; boxer's muscle

Clavicle, acromion & spine of scapula

Elevates, adducts, depresses scapula; rotates scapula upward.

Levator scapulae Rhomboid major

Superior vertebral Elevates scapula border of scapula Vertebral border of Elevates and adducts scapula and scapula inferior to rotates it downward

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Rhomboid minor

Spines of C7-T1

spine Vertebral border of As major scapula superior to spine p.357 Greater tubercle & intertubercular sulcus of humerus Intertubercular sulcus of humerus Adducts and medially rotates arm at shoulder; Flexes arm (part) Adducts and medially rotates arm at shoulder; Extends arm; draws arm inferiorly and posteriorly Abducts, flexes & medially rotates, extends & laterally rotates arm at shoulder Medially rotates arm at shoulder only Abducts arm at shoulder only (assists deltoid m.) Laterally rotates and adducts arm at shoulder (Same as latissimus dorsi) (Same as infraspinatus) Flexes and adducts arm

Move the humerus Pectoralis major Clavicle, sternum, costal cartilages of 2-6 ribs Latissimus dorsi Spine of T7-L5, thoracolumbar fascia, iliac rest, lower 4 ribs Deltoid Lateral third of clavicle, acromion & spine of scapula Subscapularis Subscapular fossa of scapula Supraspinatus Supraspinous fossa of scapula Infraspinatus Infraspinous fossa of scapula Teres major Teres minor Coracobrachialis Forearm Flexors Biceps brachii Inferior angle of scapula Lateral border of scapula Coracoid process of scapula

Deltoid tuberosity of humerus Lesser tubercle of humerus Greater tubercle of humerus Greater tubercle of humerus Intertubercular sulcus of humerus Greater tubercle of humerus Middle of medial shaft of humerus

Brachialis Brachioradialis

Supraglenoid tubercle of scapula (long head), coracoid process (short head) Distal, ant. Surface of humerus Lateral border of distal humerus

p.363 Radial tuberosity & Flexes forearm, supinates forearm, bicipital aponeurosis flexes arm

Ulna tuberosity & coronoid process Superior to styloid process of radius

Major flexor of forearm Flexes forearm, supinates & pronates forearm to neutral position

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Forearm Extensors Triceps brachii

Infraglenoid Olecranon process tubercle of scapula, medial & lateral surfaces of humerus

Extends forearm & arm

Forearm Pronators Pronator teres and quadratus Forearm supinator Supinator MUSCLES THAT MOVE THE WRIST, HAND, AND DIGITS

p.363

p.369

Superficial Anterior Compartment (flexors) All originate from the medial epicondyle of the humerus (also, pronator teres) Flexor carpi radialis flexes and abducts hand at wrist Palmaris longus Flexor carpi ulnaris flexes and adducts hand at wrist Flexor digitorum superficialis flexes proximal and middle phalanx of each finger Deep Anterior Compartment (flexors) Flexor pollicis longus Flexor digitorum profundus

flexes distal phalanx of thumb flexes proximal, middle and distal phalanx

Superficial Posterior Compartment (Extensors) All originate from the lateral epicondyle of the humerus (also, supinators) Extensor carpi radialis longus extends and abducts hand at wrist Extensor carpi radialis brevis Extensor digitorum Extensor digiti minimi extends proximal phalanx of little finger Extensor carpi ulnaris extends and adducts hand at wrist Deep Posterior Compartment (Extensors) Abductor pollicis longus Extensor pollicis brevis, longus Extensor indicis extends index finger INNERVATION p.597 Brachial Plexus Formed by the anterior rami of spinal nerves of C5-C8 and T1 Provides the entire nerve supply of the shoulder and upper limb There are four major branches of this plexus Roots ­ five ventral rami (C5-T1) Trunks ­ upper, middle, and lower, which form divisions

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Divisions ­ anterior and posterior serve the front and back of the limb Cords ­ lateral, medial, and posterior fiber bundles Five important nerves arise from the brachial plexus: - Lateral cord: musculocutaneous & part of median nerves. - Medial cord: part of median nerve & ulnar. - Posterior cord: axillary & radial. Nerve Axillary Musculocutaneous Radial Median Origin Distribution C5-C6 Deltoid, teres minor C5-C7 Flexors: coracobrachialis, biceps brachii, & brachialis C5-C8, Essentially all extensor T1 muscles C5-C8, Flexors of forearm except T1 flexor carpi ulnaris and ulnar half of flexor digitorum profundus C8-T1 Injury

Wrist drop

Ulnar

Dorsal scapular Long thoracic Suprascapular Thoracodorsal Upper subscapular Lower subscapular Lateral pectoral Medial pectoral CIRCULATION

Median nerve palsy: numbness, tingling, pain in palm and fingers; inability to pronate the forearm and flex the proximal interphalangeal joint Flexor carpi ulnaris & part Clawhand: inability to adduct or of the flexor digitorum abduct the four fingers (not the profundus; most of the hand thumb), loss of sensation of the muscles little finger Levator scapula, rhomboid major & minor Anterior serratus Winged scapula: paralysis of the serratus anterior Supraspinatus & infraspinatus Latissimus dorsi Subscapularis Subscapularis, teres major Pectoralis major Pectoralis major, minor p.497

Subclavian a. axillary a. brachial a. radial a. and ulnar a. superficial and deep palmar arches Superficial veins: lateral (cephalic v.) medial (basilic v.), connected within cubital fossa by median cubital v. Deep veins: accompany arteries; have same names.

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LABORATORY IDENTIFICATION I. SKELETAL SYSTEM 1. Clavicle a. acromial end b. sternal end c. conoid tubercle d. right vs. left 2. Scapula a. acromion b. coracoid process c. spine d. borders: medial (vertebral), lateral (axillary), superior e. fossa: subscapular, supraspinous, infraspinous f. glenoid cavity g. scapular notch h. angles: superior, inferior i. right vs. left 3. Humerus: a. head b. neck: anatomical neck, surgical neck c. tubercles: greater, lesser d. intertubercular sulcus e. condyles: capitulum, trochlear f. epicondyles: lateral, medial g. deltoid tuberosity h. coronoid fossa i. olecranon fossa j. right vs. left 4. Radius: a. head b. neck c. radial tuberosity d. dorsal tubercle e. radial styloid process f. right vs. left 5. Ulna: a. olecranon b. trochlear notch c. radial notch d. coronoid process e. ulnar styloid process f. right vs. left 6. Carpal bones: a. proximal row (lateral to medial): scaphoid, lunate, triquetrum, pisiform (pea) b. distal row (lateral to medial); trapezium, trapezoid, capitate, hamate (hook) 7. Metacarpal bones: I, II, III, IV & V. 8. Phalanges: proximal, middle, distal: I, II, III, IV & V. (no middle phalanx of digit I) II. Joints 1. Shoulder Joint Model (Glenohumeral joint and acromioclavicular joint): a. coracoacromial ligament, b. coracoclavicular ligament c. acromioclavicular ligament d. tendon of the long head of the biceps brachii e. tendon of subscapularis, tendon of infraspinatus, f. supraspinatus muscle g. bursa: subacromial, subcoracoid h. articular capsule 2. Wrist Joint: (on forearm models) a. flexor retinaculum b. extensor retinaculum

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Identify the following structures on Models and Cadavers UPPER LIMB MUSCELS BACK MUSCLES 1. pectoralis minor 33. levator scapulae 2. serratus anterior 34. erector spinae - iliocostalis 3. trapezius 35. erector spinae - longissimus 4. levator scapulae 36. erector spinae - spinalis 5. rhomboid (major, minor) 37. splenius capitis 6. pectoralis major 38. semispinalis capitis 7. latissimus dorsi 8. deltoid 9. supraspinatus 10. infraspinatus 11. teres minor 12. teres major 13. coracobrachialis 14. subscapularis 15. biceps brachii 16. brachialis 17. triceps brachii 18. brachioradialis 19. pronator teres 20. flexor carpi radialis 21. palmaris longus 22. flexor carpi ulnaris 23. extensor carpi radialis (a. longus, b. brevis) 24. extensor carpi ulnaris 25. flexor digitorum superficialis 26. flexor digitorum profundus 27. extensor digitorum 28. thenar eminence (area) 29. hypothenar eminence (area) 30. abductor pollicis longus 31. extensor pollicis brevis 32. extensor pollicis longus (tendon) UPPRE LIMB NERVES 39. axillary n. 40. radial n. 41. median n. 42. ulnar n. UPPER LIMB ARTERIES 47. axillary a. 48. brachial a. 49. ulnar a. 50. radial a.

43. lateral cord 44. medial cord 45. posterior cord 46. musculocutaneous n. VEINS 51. cephalic v. 52. basilic v. 53. median cubital v. 54. axillary vein 55. superficial palmar arch

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LOWER LIMB REGION Development: During development the lower limb rotates medially. After rotation the big toe is located on the medial side of the digits of the foot. The lower limb flexors for the knee and ankle are located on the posterior surface and lower limb extensors are located on the anterior surface. Functions of the lower limb: weight bearing and stability Pelvic Girdle (Hip) Chapter 8, p.228 The hip is formed by a pair of hip bones (os coxae, or coxal) Together with the sacrum and the coccyx, these bones form the bony pelvis Ilium The ilium is a large flaring bone that forms the superior region of the coxal bone Articulates with the sacrum (sacroiliac joint) Major markings include the iliac crests, four spines, greater sciatic notch, iliac fossa, and the pelvic brim Ischium The ischium forms the posteroinferior part of the hip bone The thick body articulates with the ilium, and the thinner ramus articulates with the pubis Major markings include the ischial spine, lesser sciatic notch, and the ischial tuberosity Pubis The pubic bone forms the anterior portion of the hip bone It articulates with the ischium and the ilium Major markings include superior and inferior rami, pubic tubercle, pubic arch, pubic symphysis, and obturator foramen (along with ilium and ischium) The Lower Limb The three segments of the lower limb are the thigh, leg, and foot They carry the weight of the erect body, and are subjected to exceptional forces when one jumps or runs Femur The sole bone of the thigh is the femur, the largest and strongest bone in the body It articulates proximally with the hip and distally with the tibia and fibula Major markings include the head, fovea capitis, greater and lesser trochanters, gluteal tuberosity, lateral and medial condyles and epicondyles, linea aspera, and the intercondylar fossa Leg The tibia and fibula form the skeleton of the leg They are connected to each other by the interosseous membrane They articulate with the femur proximally and with the ankle bones distally Tibia Receives the weight of the body from the femur and transmits it to the foot Major markings include medial and lateral condyles, intercondylar eminence, the tibial tuberosity, and medial malleolus Fibula

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Sticklike bone with slightly expanded ends located laterally to the tibia Major markings include the head and lateral malleolus Foot The skeleton of the foot includes the tarsus, metatarsus, and the phalanges (toes) The foot supports body weight and acts as a lever to propel the body forward in walking and running Tarsus Composed of seven bones that form the posterior half of the foot Body weight is carried primarily on the talus and calcaneus Talus articulates with the tibia and fibula superiorly, and the calcaneus inferiorly Other tarsus bones include the cuboid and navicular, and the medial, intermediate, and lateral cuneiforms Metatarsals Five (1-5) long bones that articulate with the proximal phalanges Phalanges The 14 bones of the toes Each digit has three phalanges except the hallux, which has no middle phalanx ARTICULATIONS Hip (Coxal) Joint p. 274 Ball-and-socket joint Head of the femur articulates with the acetabulum Good range of motion, but limited by the deep socket and strong ligaments Synovial Joints: Hip Stability Articular capsule Acetabular labrum Iliofemoral ligament Pubofemoral ligament Ischiofemoral ligament Ligament of the head of the femur Knee joint: p.277 - The largest and most complex joint of the body, consisting of 3 joints within a single synovial cavity: an intermediate patellofemoral joint, a lateral tibiofemoral joint, and a medial tibiofemoral joint. Articular capsule Tibial and fibular collateral ligament: prevent side-to-side movement. Anterior Cruciate ligament: limits the hyperextension of the knee and prevents the anterior sliding of the tibia on the femur. Posterior cruciate ligament: prevents the posterior sliding of the tibia on the femur. The most common type of knee injury in football usually involves three structures, which sometimes refer as the unhappy triad. These structures are: 1. rupture of tibial collateral ligament, associated with tearing of anterior cruciate ligament, and 3. medial meniscus. P. 279

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MUSCULAR SYSTEM Muscle Move the femur Iliopsoas Psoas major Iliacus Gluteus maximus Origin Insertion

p.358 Action

Lumbar vertebrae Iliac fossa Iliac crest, sacrum, coccyx Ilium Iliac crest Anterior sacrum

Lesser trochanter of femur Iliotibial tract & linea aspera (gluteal tuberosity) Greater trochanter of femur Tibia by way of iliotibial tract Greater trochanter of femur

Flex thigh, laterally rotate thigh Extends thigh, laterally rotates thigh Abducts thigh, medially rotates thigh

Gluteus medius Tensor fasciae latae Piriformis

Abducts thigh, laterally rotates thigh

Medial compartment Adductor longus Gracilis Adductor manus Anterior compartment Quadriceps femoris Rectus femoris Vastus lateralis Pubic symphysis Inferior ramus of pubic Inferior ramus of pubic & ischium Linea aspera Medial of tibia Linea aspera Adducts and flexes thigh

Ant. Inf. iliac Patella via quadriceps spine tendon and then tibial Greater trochanter &linea aspera patellar tuberosity via Linea aspera ligament Linea aspera Ant. femur Ant. sup. iliac spine

All four heads extends leg at knee Joint; (rectus femoris Alone also flexes Thigh)

Vastus medialis Vastus intermedius Sartorius

Medial surface of tibia

Flexes leg at knee. Flexes, abducts, laterally rotates thigh

Posterior compartment Hamstrings Long head: ischial Biceps femoris tuberosity; short head: linea aspera

Head of fibula

All three: flexes leg And extends thigh

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Semitendinosus Semimembranosus Move foot & toes Anterior compartment Tibialis anterior

Ischial tuberosity Ischial tuberosity

Medial surface & condyle of tibia

Lateral condyle & body of tibia

1st cuneiform & 1st metatarsal

Dorsiflexes foot inverts foot Dorsiflexes foot & Extends great toe Dorsiflexes foot & Extends toes

Extensor hallucis longus Extensor digitorum longus Lateral compartment Peroneus (fibularis) longus

Head & body of fibula, lateral condyle of tibia

1st metatarsal & 1st cuneiform

Both muscles plantar flex foot & evert foot

Peroneus (fibularis) brevis Posterior compartment Superficial: Gastrocnemius Lateral and medial condyles of femur Soleus head of fibula & medial border of tibia

Calcaneus by way of calcaneal (Achilles) tendon (both muscles)

Both: Plantar flexes foot

Deep: Tibialis posterior Flexor digitorum longus Flexor hallucis longus

Plantar flexes foot & inverts foot Plantar flexes foot & flexes toes Plantar flexes foot & flexes great toe

INNERVATION p.600 Lumbar plexus - Anterior rami of spinal nerves L1-L4. - Supplies the anterolateral abdominal wall, external genitals, and part of the lower extremity. The major nerves are the femoral and the obturator Femoral nerve - Deep to inguinal ligament, lateral to femoral artery. - Supplies flexors of thigh, extensors of leg; skin on front and medial thigh, medial leg and foot. - Injury: inability to extend the leg and loss of sensation in the skin over anteromedial thigh. Obturator nerve - Through obturator foramen. - Supplies adductor muscles of leg, skin over medial thigh.

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Sacral Plexus Arises from L4-S4 and serves the buttock, lower limb, pelvic structures, and the perineum The major nerve is the sciatic, the longest and thickest nerve of the body The sciatic is actually composed of two nerves: the tibial and the common fibular (peroneal) nerves - Supplies the buttock, perineum, and lower extremities. Superior gluteal nerve: gluteus minimus and medius; tensor fasciae latae. Inferior gluteal nerve: gluteus maximus. Sciatic nerve: hamstring muscles & adductor magnus. Tibial nerve: flexor muscles in the posterior compartment of leg. Common peroneal (fibular) nerve: lateral (superficial peroneal) and anterior compartments (deep peroneal) of leg; injury: footdrop. Sciatica: a type of neuritis characterized by severe pain along the path of the sciatic nerve and its branches. Inflammation and infection; most common cause: herniated disc. Intramuscular (IM) injection sites: Gluteus medius, vastus lateralis, and deltoid CIRCULATION: p. 526 Arteries: common iliac a. internal and external iliac a. external iliac a. femoral a. popliteal a. anterior and posterior tibial a. Deep veins: accompany arteries; have the same names; subject to formation of deep vein thrombosis. Superficial veins: Great saphenous vein - The longest vein in the body - Medial side of lower limb; empties into femoral vein at femoral triangle. - Subject to becoming varicose with formation of clots. - Is used in coronary bypass surgery. - Are often used for prolonged IV. Small (short) saphenous vein: - Lateral side, empties into popliteal veins in the popliteal fossa. Femoral triangle: p.433 Boundaries: Superior-medial: inguinal ligament Lateral: sartorius Inferior-medial: adductor longus Floor: iliopsoas Contents (medial ­ lateral): VAN (femoral vein, artery, nerve), deep inguinal lymph nodes, and entrance of great saphenous vein. Popliteal fossa: (diamond-shaped space) Boundaries: superior (medial: semitendinosus, semimembranosus; lateral: biceps femoris) Inferior: gastrocnemius Contents: popliteal artery and vein; bifurcation of sciatic nerve into tibial and common fibular nerve; entrance of small saphenous vein.

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LABORATORY IDENTIFICATION I. SKELETAL SYSTEM 1. Hip (coxal, os coxa) bone a. three parts: ilium, ischium, pubis b. ilium: iliac crest, anterior (superior, inferior) iliac spine, iliac fossa, greater sciatic notch. c. ischium: ischial tuberosity, lesser sciatic notch, ischial spine, obturator foramen, ischial ramus d. pubis: pubic tubercle, superior pubic ramus, inferior pubic ramus e. acetabulum (is the socket formed where the three part of the hip bone converge) f. 2. Femur a. b. c. d. f. h. 3. Patella 4. Tibia right vs. left head: fovea for ligament of head (fovea capitis) neck greater trochanter; lesser trochanter gluteal tuberosity e. linea aspera condyles (medial, lateral) g. intercondylar fossa right vs. left

a. condyles (medial, lateral) c. tibial tuberosity e. right vs. left 5. Fibula

b. intercondylar eminence d. medial malleolus

a. head b. lateral malleolus c. right vs. left 6. Tarsal bones: Talus, calcaneus, cuneiforms (medial, intermediate, lateral), navicular, cuboid 7. Metatarsus: I ­ V 8. Phalanges: (as in upper limbs) II. JOINTS ­ Ligaments, Tendons, and Membrane 1. Hip joint model: Ligaments: iliofemoral, pubofemoral, ischiofemoral. Obturator membrane 2. Knee joint: Collateral ligaments (medial/tibial, lateral/fibular) Cruciate ligaments (anterior & posterior) Meniscus (medial, lateral) Patellar ligament, patella Interosseous membrane 3. Ligaments and tensons ­ inguial ligament, iliotibial tract, and calcaneal tendon Identify the following structures on the models and cadavers III. LOWER LIMB MUSCLES

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1. gluteus maximus 2. gluteus medius 3. tensor fasciae latae 4. piriformis 5. iliacus 6. psoas major 7. rectus femoris 8. sartorius 9. vastus medialis 10. vastus lateralis 11. adductor longus 12. adductor magnus 13. gracilis 14. biceps femoris 15. semitendinosus 16. semimembranosus 17. tibialis anterior 18. extensor digitorum longus 19. extensor hallucis longus 20. fibularis longus 21. gastrocnemius 22. soleus 23. flexor digitorum longus 24. flexor hallucis longus 25. tibialis posterior IV. LOWER LIMB NERVES 26. obturator N 27. femoral N 28. sciatic N V. LOWER LIMB ARTERIES 32. external iliac A internal iliac A 33. femoral A 34. deep femoral A 34. popliteal A 35. anterior tibial A 36. posterior tibial A 37. superior gluteal A 38. inferior glutea A VI. LOWER LIMB VEINS 39. external iliac V 41. femoral V

29. tibial N 30. common fibular N 31. deep fibular N

40. popliteal V 42. great saphenous V

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HEAD AND NECK REGIONS Skeletal System The Skull p.165 The skull, the body's most complex bony structure, is formed by the cranium and facial bones Cranium ­ protects the brain and is the site of attachment for head and neck muscles Facial bones Supply the framework of the face, the sense organs, and the teeth Provide openings for the passage of air and food Anchor the facial muscles of expression Anatomy of the Cranium Eight cranial bones ­ two parietal, two temporal, frontal, occipital, sphenoid, and ethmoid Cranial bones are thin and remarkably strong for their weight Frontal Bone Forms the anterior portion of the cranium Articulates posteriorly with the parietal bones via the coronal suture Major markings include the supraorbital margins, the anterior cranial fossa, and the frontal sinuses (internal and lateral to the glabella) Parietal Bones and Major Associated Sutures Form most of the superior and lateral aspects of the skull Four sutures mark the articulations of the parietal bones Coronal suture ­ articulation between parietal bones and frontal bone anteriorly Sagittal suture ­ where right and left parietal bones meet superiorly Lambdoid suture ­ where parietal bones meet the occipital bone posteriorly Squamosal or squamous suture ­ where parietal and temporal bones meet Occipital Bone Forms most of skull's posterior wall and base Major markings include the posterior cranial fossa, foramen magnum, occipital condyles, and the hypoglossal canal Temporal Bones Form the inferolateral aspects of the skull and parts of the cranial floor Divided into four major regions ­ squamous, tympanic, mastoid, and petrous Major markings include the zygomatic, styloid, and mastoid processes, and the mandibular and middle cranial fossae Major openings include the stylomastoid and jugular foramina, the external and internal auditory meatuses, and the carotid canal Sphenoid Bone Butterfly-shaped bone that spans the width of the middle cranial fossa Forms the central wedge that articulates with all other cranial bones Consists of a central body, greater wings, lesser wings, and pterygoid processes Major markings: the sella turcica, hypophyseal fossa, and the pterygoid processes Major openings include the foramina rotundum, ovale, and spinosum; the optic canals; and the superior orbital fissure Ethmoid Bone Most deep of the skull bones; lies between the sphenoid and nasal bones Forms most of the bony area between the nasal cavity and the orbits

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Major markings include the cribriform plate, crista galli, perpendicular plate, nasal conchae, and the ethmoid sinuses Facial Bones Fourteen bones of which only the mandible and vomer are unpaired The paired bones are the maxillae, zygomatics, nasals, lacrimals, palatines, and inferior conchae Mandible The mandible (lower jawbone) is the largest, strongest bone of the face Its major markings include the coronoid process, mandibular condyle, the alveolar processes, and the mandibular and mental foramina Maxillary Bones Medially fused bones that make up the upper jaw and the central portion of the facial skeleton Facial keystone bones that articulate with all other facial bones except the mandible Their major markings include palatine, frontal, and zygomatic processes, the alveolar processes, inferior orbital fissure, and the maxillary sinuses Zygomatic Bones Irregularly shaped bones (cheekbones) that form the prominences of the cheeks and the inferolateral margins of the orbits Other Facial Bones Nasal bones ­ thin medially fused bones that form the bridge of the nose Lacrimal bones ­ contribute to the medial walls of the orbit and contain a deep groove called the lacrimal fossa that houses the lacrimal sac Palatine bones ­ two bone plates that form portions of the hard palate, the posterolateral walls of the nasal cavity, and a small part of the orbits Vomer ­ plow-shaped bone that forms part of the nasal septum Inferior nasal conchae ­ paired, curved bones in the nasal cavity that form part of the lateral walls of the nasal cavity Orbits Bony cavities in which the eyes are firmly encased and cushioned by fatty tissue Formed by parts of seven bones ­ frontal, sphenoid, zygomatic, maxilla, palatine, lacrimal, and ethmoid Paranasal Sinuses Mucosa-lined, air-filled sacs found in five skull bones ­ the frontal, sphenoid, ethmoid, and paired maxillary bones Air enters the paranasal sinuses from the nasal cavity and mucus drains into the nasal cavity from the sinuses Lighten the skull and enhance the resonance of the voice Hyoid Bone Not actually part of the skull, but lies just inferior to the mandible in the anterior neck Only bone of the body that does not articulate directly with another bone Attachment point for neck muscles that raise and lower the larynx during swallowing and speech Covering of the skull ­ Scalp S = skin C = CT dense

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A = aponeurosis L = CT loose P = periosteum (outer) Diploe (middle) Inner periosteum: fused with meningeal dura at places to form cranial dura Where dura is un-fused with periosteum blood collection area: sinuses Fetal Skull Fontanels = soft spots; junction of 2 or more sutures connected by fibrous CT; close 18 month ­ 2 years old. P.190 - Anterior (frontal): between the 2 parietal bones and the frontal bone. - Posterior (occipital): between the 2 parietal bones and the occipital bone. - Anterolateral (sphenoid): between the frontal, parietal, temporal, and sphenoid bones. - Posterolateral (mastoid): between the parietal, occipital, and temporal bones. Articulation TMJ (temporomandibular joint) p.268 Combined hinge and planar joint formed by the condylar process of the mandible and the mandibular fossa and articular tubercle of the temporal bone. The only movable joint between the skull bones. Depression, elevation, protraction, retraction, laterals gliding. Atlanto-occipital p.266 Between skull and atlas Synovial (condyloid) Flexion and extension of head; say, Yes. Atlanto-axial Between dens of axis and arch of atlas Synovial (pivot) Rotation of head; say No Muscular System Muscles of Facial Expression p.318 When they contract, muscles move the skin rather than a joint 1. Frontalis draws scalp anteriorly, raises eyebrow, wrinkles skin 2. Occipitalis draws scalp posteriorly 3. Orbicularis oris closes and protrudes lips 4. Zygomaticus major draws angle of mouth superiorly & laterally, as in smiling 5. Buccinator presses cheeks against teeth and lips, as in whistling, blowing, sucking 6. Platysma depresses mandible 7. Orbicularis oculi closes eye Muscles of Mastication 8. Masseter elevates & retracts mandible 9. Temporalis 10. Medial pterygoid elevates & protracts mandible 11. Lateral pterygoid depresses & protracts mandible Suprahyoid (Submandibular) p.330 12. Digastric elevates hyoid bone and depresses mandible

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13. Mylohyoid as digastric Infrahyoid muscles 14. Omohyoid 15. Sternohyoid 14 & 15 both depress hyoid bone 16. Sternothyroid depresses thyroid cartilage of larynx 17. Thyrohyoid elevates thyroid cartilage & depresses hyoid bone Muscles of the Neck p.331 18. Sternocleidomastoid bilaterally: flex cervical vertebrae, extend head; unilaterally: lateral flex and rotate head to side opposite contracting muscle 19. Trapezius Scalene Muscles bilaterally: flex head and; unilaterally: lateral flex and rotate head to side opposite contracting muscle. 20. Anterior 21. middle 22. posterior Eye muscles p.324 Superior rectus moves eyeball superiorly and medially Inferior rectus moves eyeball inferiorly and medially Lateral rectus moves eyeball laterally Medial rectus moves eyeball medially Superior oblique moves eyeball inferiorly and laterally Inferior oblique moves eyeball superiorly and laterally Triangles p.311 The sternocleidomastoid muscle divides the neck into two major triangles: Anterior Triangle is bordered Superiorly: mandible Inferiorly: sternum Medially: cervical midline Laterally: anterior border of the sternocleidomastoid Contains: lymph nodes, submandibular and parotid salivary glands, facial artery and vein, carotid arteries and internal jugular vein, cranial nerves IX, X, XI and XII. Posterior Triangle Inferiorly: clavicle Anteriorly: posterior border of the sternocleidomastoid Posteriorly: trapezius Contains: lymph nodes, subclavian artery, external jugular vein, brachial plexus and CN XI Circulation p.499 Common carotid A: At superior border of the larynx, it divides external and internal carotid arteries A carotid pulse may be detected just lateral to the larynx. External carotid A: At TMJ joint, divides into the superficial temporal and maxillary arteries. Supply structures external to the skull. Internal carotid A:

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Has no branches in the neck and supplies structures internal to the skull. Terminal branches: anterior cerebral artery and middle cerebral artery. Anastomoses of the left and right internal carotid arteries along with the basilar artery form Circle of Willis (cerebral arterial circle) Anterior cerebral arteries (branches of internal carotid) Posterior cerebral arteries (branches of basilar a) Anterior communicating a Posterior communication a Internal carotid a. The functions are to equalize blood pressure to the brain and provide alternate routes for blood flow to the brain, should the arteries become damaged Dural Venous sinuses: into the internal jugular veins a. superior sagittal b. inferior sagittal c. straight sinus d. transverse sinus e. sigmoid f. cavernous sinus: CN III, IV, V & internal carotid arteries pass through. Meninges p.613 Dura, arachnoid, pia mater. Three dural septa extend inward and limit excessive movement of the brain Falx cerebri ­ fold that dips into the longitudinal fissure Falx cerebelli ­ runs along the vermis of the cerebellum Tentorium cerebelli ­ horizontal dural fold extends into the transverse fissure Blood-Brain Barrier Protective mechanism that helps maintain a stable environment for the brain Bloodborne substances are separated from neurons by: Continuous endothelium of capillary walls Relatively thick basal lamina Bulbous feet of astrocytes Blood-Brain Barrier: Functions Selective barrier that allows nutrients to pass freely Is ineffective against substances that can diffuse through plasma membranes Absent in some areas (vomiting center and the hypothalamus), allowing these areas to monitor the chemical composition of the blood Cerebrospinal Fluid (CSF) p.616 Choroid Plexuses Clusters of capillaries that form tissue fluid filters, which hang from the roof of each ventricle Cerebrospinal fluid (CSF) CSF: Watery solution similar in composition to plasma, but less protein Provide mechanical, chemical protections and circulation. Is called Blood-cerebrospinal fluid barrier

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A lateral ventricle is located in each hemisphere of the cerebrum, separated by septum pellucidum. The third ventricle is between the left and right halves of the thalamus. The lateral ventricles connect to the third ventricle via the interventricular foramen. The third and fourth ventricles are linked by the cerebral aqueduct The fourth ventricle lies between the brain stem and the cerebellum. The walls of all of the ventricles contain choroid plexus (networks of capillaries, and covered by ependymal cells) that produce CSF: Lateral v. third v. cerebral aqueduct fourth v. to subarachnoid space and central canal of spinal cord CSF is gradually reabsorbed into the blood through arachnoid villi, fingerlike extension of the arachnoid that project into the dural venous sinuses. Hydrocephalus: excess CSF accumulation pressure increase destruction of brain tissue. Treatment: shunt to subclavian vein or peritoneal space Brain Stem p.620 Consists of three regions ­ midbrain, pons, and medulla oblongata Similar to spinal cord but contains embedded nuclei Controls automatic behaviors necessary for survival Provides the pathway for tracts between higher and lower brain centers Associated with 10 of the 12 pairs of cranial nerves Medullar Oblongata Most inferior part of the brain stem Five pairs of cranial nerves originate from here (VIII to XII) Pyramids ­ two longitudinal ridges formed by corticospinal tracts Decussation of the pyramids ­ crossover points of the corticospinal tracts Cardiovascular control center ­ adjusts force and rate of heart contraction Respiratory centers ­ control rate and depth of breathing Reflex centers: sneezing, coughing, swallowing, and vomiting Pons Bulging brainstem region between the midbrain and the medulla oblongata Fibers of the pons: Connect higher brain centers and the spinal cord Relay impulses between the motor cortex and the cerebellum Origin of cranial nerves V (trigeminal), VI (abducens), VII (facial), and VIII Contains nuclei of the reticular formation Minor respiratory centers Midbrain (mesencephalon) Located between the diencephalon and the pons Midbrain structures include: Cerebral peduncles ­ two bulging structures that contain descending pyramidal motor tracts Cerebral aqueduct ­ hollow tube that connects the third and fourth ventricles Midbrain Nuclei Nuclei that control cranial nerves III (oculomotor) and IV (trochlear) Tectum ­ four domelike protrusions of the dorsal midbrain

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Superior colliculi ­ visual reflex centers Inferior colliculi ­ auditory relay centers Substantia nigra: neurons that release dopamine extend from the substantia nigra to the basal ganglia and help control subconscious muscle activities. Loss of these neurons is associated with Parkinson's disease. Red nucleus ­ largest nucleus of the reticular formation; red nuclei are relay nuclei for some descending motor pathways Reticular Formation Gray matter network among threads of white matter in brainstem, spinal cord & thalamus. Alerting the cerebral cortex to incoming sensory signals. Reticular activating system (RAS): maintaining consciousness and awakening from sleep. THE CEREBELLUM p.625 Consists of Vermis and cerebellar hemispheres Is separated from the cerebrum by the transverse fissure, and by the tentorium cerebelli. Coordinating skilled movements. Regulating posture and balance Makes up 11% of the brain's mass Cerebellar activity occurs subconsciously THE DIENCEPHALON p.627 Extends from the brain stem to the cerebrum and surrounds the third ventricle; It includes thalamus, hypothalamus, and epithalamus Thalamus Makes up 80% of the diencephalons A bridge of gray matter called the intermediate mass joins the right and left halves Internal capsule: axons that connect the thalamus and cerebral cortex pass through it, a thick band of white matter lateral to the thalamus Sensory relay center Allows for crude sensory awareness Positively reinforces voluntary motor activity Hypothalamus Located below the thalamus, it caps the brainstem and forms the inferolateral walls of the third ventricle Mammillary bodies Small, paired nuclei bulging anteriorly from the hypothalamus Relay station for olfactory pathways Infundibulum ­ stalk of the hypothalamus; connects to the pituitary gland Main visceral control center of the body: Hypothalamic Nuclei Hypothalamic Function Regulates blood pressure, rate and force of heartbeat, digestive tract motility, rate and depth of breathing, and many other visceral activities Is involved with perception of pleasure, fear, and rage Controls mechanisms needed to maintain normal body temperature Regulates feelings of hunger and satiety

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Regulates sleep and the sleep cycle Endocrine Functions of the Hypothalamus Epithalamus Consists of habenular nuclei and Pineal gland: secretes melatonin (promote sleepiness) THE CEREBRUM p.630 The outer rim of gray matter is the cerebral cortex. The deepest grooves as fissures, the shallower grooves are sulci, the folds are gyri. The longitudinal fissure separates the cerebrum into right and left halves called cerebral hemispheres, separated by falx cerebri. The hemispheres are connected internally by the corpus callosum (white matter). Lobes of the Cerebrum The central sulcus separates the frontal lobe from the parietal lobe. The lateral cerebral sulcus separates the frontal lobe from the temporal lobe. The parieto-occipital sulcus separates the parietal lobe. Insula: lies within the lateral sulcus. Cerebral White Matter 1. Association tracts contain axons that conduct nerve impulses between gyri in the same hemisphere. 2. Commissural tracts contain axons that conduct nerve impulses from gyri in one cerebral hemisphere to corresponding gyri in the other cerebral hemisphere, such as corpus callosum 3. Projection tracts from the cerebrum to lower parts of the CNS or from lower parts of CNS to the cerebrum, such as internal capsule. Frontal Lobes: p.636 1. Primary Motor Cortex (area 4 in K. Brodmann's map f the cerebral cortex) Located in the precentral gyrus Composed of pyramidal cells whose axons make up the corticospinal tracts Allows conscious control of precise, skilled, voluntary movements 2. Premotor Cortex Located anterior to the precentral gyrus Controls learned, repetitious, or patterned motor skills Coordinates simultaneous or sequential actions Involved in the planning of movements 3. Broca's speech Area (areas 44 and 45) Located anterior to the inferior region of the premotor area Present in one hemisphere (usually the left, 97% population) A motor speech area that directs muscles of the tongue Is active as one prepares to speak Lesion: person can still have clear thoughts, but are unable to form word, nonfluent aphasia

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4. Prefrontal Cortex Located in the anterior portion of the frontal lobe Involved with intellect, cognition, recall, and personality Necessary for judgment, reasoning, persistence, and conscience Parietal Lobes: 1. Primary Somatosensory Cortex (areas 1, 2, and 3) Located in the postcentral gyrus, this area: Receives information from the skin and skeletal muscles: touch, proprioception, temperature, and pain 2. Somatosensory Association Cortex Located posterior to the primary somatosensory cortex Integrates sensory information Forms comprehensive understanding of the stimulus Occipital Lobes: 1. Primary visual (striate) cortex Seen on the extreme posterior tip of the occipital lobe Receives visual information from the retinas 2. Visual association area Surrounds the primary visual cortex Interprets visual stimuli (e.g., color, form, and movement) Temporal Lobes: 1. Primary auditory cortex Located at the superior margin of the temporal lobe Receives information related to pitch, rhythm, and loudness Auditory association area Located posterior to the primary auditory cortex Stores memories of sounds and permits perception of sounds 2. Speech: Wernicke's area: (22, 39, and 40) Left temporal and parietal lobes Allows for comprehension of written/spoken word Lesion: can still speak, but cannot arrange words in a coherent fashion, fluent aphasia or "word salad". 3. Olfactory SUBCORTICAL REGIONS Basal ganglia p.632 Three nuclei buried deep in white matter in parts of thalamus, cerebrum and midbrain Selects purposeful activity, suppresses unwanted activity Inhibits muscle tone Monitors/coordinates slow, sustained contractions Inhibits thalamus Parkinson's: 1. Resting tremors 2. Rigidity 3. Difficulty initiating new movement 4. Bradykinesia and hypokinesia

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The Limbic System A ring of structures encircling the upper part of the brain stem and the corpus callosum Includes the rhinencephalon, amygdala, hypothalamus, and anterior nucleus of the thalamus Motivation, Memory, Emotional behavior Cerebrovascuar Accident (CVA)/Stroke p.639

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The Autonomic Nervous System

A. Introduction Chapter 20, p. 659

1. The autonomic nervous system (ANS) regulates the activity of smooth muscle, cardiac muscle, and certain glands. 2. The ANS includes: i. autonomic sensory neurons ii. integrating centers in the CNS iii. autonomic motor neurons iv. enteric division located in the wall of the gastrointestinal system 3. The ANS is regulated by centers in the brain, primarily the hypothalamus and brain stem. B. Comparison of Somatic and Autonomic Nervous Systems 1. In the somatic nervous system: i. sensory neurons transmit information from receptors for the special senses and somatic senses ii. these sensations are (normally) consciously perceived iii. somatic motor neurons innervate skeletal muscle to cause excitation, i.e., contraction, and therefore produce voluntary movement iv. each somatic motor pathway consists of a single somatic motor neuron that extends from the CNS to skeletal muscle v. somatic motor neurons release acetylcholine (ACh) 2. In the autonomic nervous system: i. autonomic visceral (sensory) neurons transmit information from interoceptors, such as chemoreceptors ii. the sensations are usually not consciously perceived iii. autonomic motor neurons innervate smooth muscle, cardiac muscle, and glands to: a. produce activities that are usually not under conscious control b. cause excitation or inhibition of effector tissue activity iv. autonomic motor pathways consist of sets of two motor neurons in series: a. the first neuron has its cell body in the CNS and its myelinated axon extends from the CNS to an autonomic ganglion b. the second neuron has its cell body in the autonomic ganglion and its unmyelinated axon extends directly to the autonomic effector v. autonomic motor neurons release either acetylcholine or norepinephrine (NE) vi. the output (motor) part of the ANS has two divisions: a. sympathetic division which is often called the fight-or-flight division b. parasympathetic division which is often called the rest-and-digest division - most autonomic effectors have dual innervation

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3. Table 20.1 provides an excellent summary of the similarities and differences between the somatic and autonomic nervous systems. C. Anatomy of Autonomic Motor Pathways 1. Anatomical components: i. The first of the two autonomic motor neurons is called a preganglionic neuron: a. its cell body is in the brain or spinal cord b. its myelinated axon exits the CNS as part of a cranial or spinal nerve, separates from the nerve, and extends to an autonomic ganglion where it synapses with a postganglionic neuron ii. The postganglionic neuron is the second of the two autonomic motor neurons and is located entirely outside the CNS: a. its cell body and dendrites are located in the autonomic ganglion, where it synapses with one or more preganglionic fibers b. its unmyelinated axon extends to a visceral effector 2. Preganglionic neurons: i. In the sympathetic division: a. preganglionic neurons have their cell bodies in the lateral gray horns of the 12 thoracic segments and the first two lumbar segments of the spinal cord b. therefore, the sympathetic division is also called the thoracolumbar division and the axons of the sympathetic preganglionic neurons are known as the thoracolumbar outflow ii. In the parasympathetic division: a. preganglionic neurons have their cell bodies located in the brain stem nuclei of four cranial nerves (III, VII, IX, and X) and in the lateral gray horns of the second through fourth sacral segments of the spinal cord b. therefore, the parasympathetic division is also called the craniosacral division and the axons of the parasympathetic preganglionic neurons are known as the craniosacral outflow Sympathetic and Parasympathetic Divisions Sympathetic Distribution Body wide: skin, sweat glands, arrector pili, adipose tissue, smooth m. of blood vessels, heart Location of pregaglionic lateral gray horn of spinal cord neuron cell bodies and thoracolumbar (T1-L2) site of outflow Ganglia Sympathetic trunk & prevertebral ganglia Ganglia location Close to CNS and distal from visceral effectors Rami communicantes White rami contain myelinated p. 672, Table 20.2 Parasympathetic Limited mainly to head and to viscera of thorax, abdomen, and pelvis. Craniosacral (CN III, VII, IX, X; S2-S4) Terminal ganglia Near or within wall of visceral effectors Neither present

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preganglionic axons, and gray rami contain unmyelinated postganglionic axons Preganglionic neurons With short axons synapse with many postganglionic neurons Postganglionic neurons With long axons that pass to many Visceral effectors Responses Fight-or-flight: pupils dilate increase heart rate and force elevate BP airway dilate blood vessels to kidneys, GI constrict blood vessels to muscles, liver, adipose dilate mobilizes fatty acids, elevates blood glucose level.

With long axons synapse with 4-5 Postganglionic neurons With short axons that pass to a single Visceral effectors Rest-and-digest Salivation Lacrimation Urination Digestion Defecation SLUDD

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CRANIAL NERVERS Number & Name I Olfactory Type, Location, Pathway, Exit Sensory; nasal mucosa->foramina in cribriform plate->olfactory bulb-> tract-> olfactory area (temporal lobe) Sensory; retina->optic f.->optic chiasm-> optic tract->thalamus-> primary visual area Motor; midbrain, Superior Orbital fissure (SOF) Motor; (smallest), midbrain, SOF Mixed; (largest), pons, ophthalmic, SOF maxillary, f. rotundum mandibular, f. ovale-> mandibular f. and mental f. Motor; pons, SOF Mixed; pons, internal auditory meatus-> stylomastoid f. Sensory; pons, internal auditory meatus Mixed; medulla, jugular f. Function Smell

II Optic III Oculomotor

IV Trochlear V Trigeminal

Vision Lesion: blindness/anopia Superior, medial & inferior rectus; Inferior oblique; movement of eyeball Superior oblique muscle Sensory: skin, muscle, mucosa, tooth, (face, neck) Motor: chewing muscles Lesion: neuralgia (pain) Lateral rectus muscle Taste: ant. 2/3 of tongue Motor: facial expression m. Lesion: Bell's palsy Equilibrium Hearing Taste: post. 1/3 of tongue Motor: elevates pharynx Pharynx, larynx, visceral organs in thorax and abdomen Sternocleidomastoid, trapezius Movement of tongue

VI Abducens VII Facial

VIII Vestibulochochlear IX Glossopharyngeal X. Vagus XI accessory XII Hypoglossal

Mixed; medulla, jugular f. Motor; medulla & C1-C5, jugular f. Motor, medulla, hypoglossal canal

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LABORATORY IDENTIFICATION I. Skeletal System: A. Cranial Bones (8 bones) Frontal (1) ­ coronal suture, supraorbital margin, supraorbital notch (foramen) Parietal (2) - sagittal suture, lambdoid suture Occipital (1) ­ foramen magnum, occipital condyle, external occipital protuberance Inside: jugular foramen, hypoglossal canal, Ethmoid (1) ­ inside of nasal cavity: middle nasal concha, perpendicular plate Inside: crista galli, cribriform plate (olfactory foramina) Sphenoid (1) ­ pterygoid processes (medial, lateral) Inside ­ sella turcica, lesser wings, greater wings, optic foramen, superior orbital fissure, foramen rotundum, foramen ovale, foramen spinosum, foramen lacerum Temporal (2) ­ squamous suture, external auditory meatus, zygomatic arch (temporal + zygomatic processes), mastoid process, mandibular fossa, styloid process, stylomastoid foramen, carotid canal, jugular foramen Inside: petrous portion, internal auditory meatus, carotid foramen, jugular foramen B. Facial bones (some of the images are in Unit 2) Maxillae (2) ­ alveolar process, infraorbital foramen, maxillary sinus Mandible (1) ­ body, ramus, angle, alveolar process, mandibular foramen, mental foramen, condylar process, coronoid process Zygomatic (2), Nasal (2), Lacrimal (2), Palatine (2), Inferior nasal concha (2), Vomer (1) C. D. E. F. Cranial Fossae: anterior, middle, posterior Sutures: coronal, sagittal, lambdoid, squamous Paranasal Sinuses: frontal, ethmoidal, sphenoidal, maxillary (images are in Unit 7) Fetal Skull: fontanelles (anterior, posterior, anterolateral, posterolateral)

II. Muscular System A. Muscles of the scalp ­ frontalis, epicranial aponeurosis, occipitalis B. Muscles of the face - zygomaticus major, buccinator, orbicularis oculi, orbicularis oris C. Muscles of mastication ­ masseter, temporalis D. Muscles of the neck Suprahyoid (Submandibular) - digastrics, mylohyoid Infrahyoid muscles ­ omohyoid, sternohyoid Lateral ­ sternocleidomastoid, scalenes (anterior, middle, posterior) E. Muscles of the eye Superior rectus Inferior rectus Lateral rectus Medial rectus Superior oblique Inferior oblique III. Circulation A. Arterial Supply 1. Common carotid artery a. External carotid artery and branches - Superior thyroid A, facial A, maxillary A, superficial temporal A b. Internal carotid - posterior communicating A. 2. Subclavian A

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- Vertebral A, basilar A, posterior cerebral A B. Venous return: 1. Venous sinuses - superior sagittal sinus, straight sinus, transverse sinus 2. Internal jugular vein, external jugular vein IV. Innervation A. Brain Model: a. cerebrum ­ cerebral hemisphere, longitudinal fissure, lateral ventricles b. cerebral cortex ­ lobes (frontal, parietal, occipital, temporal, insula), central sulcus, lateral sulcus (fissure), precentral gyrus, postcentral gyrus c. corpus callosum, septum pellucidum d. pineal gland e. thalamus & intermediate mass f. hypothalamus, mammillary body g. infundibulum, pituitary gland h. midbrain ­ cerebral aqueduct, superior colliculus, inferior colliculus i. pons j. medulla oblongata ­ fourth ventricle k. transverse sulcus, cerebellum - vermis, hemisphere, folia, arbor vitae (white matter) B. Ventricular model: Lateral ventricle (right/left), third ventricle, cerebral aqueduct, fourth ventricle, choroid plexus C. Dura matter: falx cerebri, tentorium cerebelli. D. Cranial Nerves Identify the following structures on skull, brain, and cranial floor models: Number & Name Enter or Exit of Cranial Cavity Additional Structures I Olfactory Cribriform plate Olfactory bulb, olfactory tract II Optic Optic foramen or canal Optic chiasm, optic tract

III Oculomotor IV Trochlear V Trigeminal 1) ophthalmic 2) maxillary 3) mandibular VI Abducens VII Facial VIII Vestibulochochlear IX Glossopharyngeal X. Vagus XI accessory XII Hypoglossal Superior orbital fissure Superior orbital fissure Superior orbital fissure, supraOrbital foramen/notch Foreman rotundum, infraOrbital foramen/notch Foreman ovale, mandibular Foreman, mental foreman Superior orbital fissure Internal auditory meatus, Stylomastoid foreman Internal auditory meatus Jugular foreman Jugular foreman Jugular foreman Hypoglossal canal

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THORAX AND THE RESPIRATORY SYSTEM Thorax p.195 Bony Thorax (Thoracic Cage) The thoracic cage is composed of the thoracic vertebrae dorsally, the ribs laterally, and the sternum and costal cartilages anteriorly Functions Forms a protective cage around the heart, lungs, and great blood vessels Supports the shoulder girdles and upper limbs Provides attachment for many neck, back, chest, and shoulder muscles Uses intercostal muscles to lift and depress the thorax during breathing Sternum (Breastbone) A dagger-shaped, flat bone that lies in the anterior midline of the thorax Results from the fusion of three bones ­ the superior manubrium, the body, and the inferior xiphoid process Anatomical landmarks include the jugular (suprasternal) notch, the sternal angle, and the xiphisternal joint Ribs There are twelve pairs of ribs forming the flaring sides of the thoracic cage All ribs attach posteriorly to the thoracic vertebrae The superior 7 pair (true) attach directly to the sternum via costal cartilages Ribs 8-10 (false) attach indirectly to the sternum via costal cartilage Ribs 11-12 (floating) have no anterior attachment Superior thoracic aperture (thoracic inlet): formed by T1, the 1st pair of ribs and the superior border of the manubrium. Inferior thoracic aperture (thoracic outlet): closed by diaphragm. T12 vertebra, the 11th and 12th pair of ribs, xiphoid process. Divisions: Two pleural sacs and mediastinum Mediastinum: region of the thorax between the lungs; contains heart, thymus, esophagus, trachea, bronchi, and vessels. Pleura: Musculature: p.772 External intercostals: fiber direction: downward & medial anteriorly; Elevate ribcage during inspiration. Internal intercostals: fibers: upward & medial anteriorly; Depress ribcage during forced expiration. Diaphragm: Origin: thoracic outlet; insertion: central tendon. Openings: vena caval foramen; esophageal hiatus; aortic hiatus. Innervation: phrenic nerve (C3-C5). Action: major inspiration muscle; flattens or descend during contraction increasing vertical dimension of thoracic cavity Volume increases; Pressure decreases air rushes in. Innervation:

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Anterior rami of T1 ­ T11: intercostal nerves. Circulation: Intercostal arteries: anterior and posterior connected. Bronchial arteries: supply lungs with oxygenated blood. Venous drainage: Azygos vein: right posterior thorax; Hemiazygos vein: left posterior inferior thorax; Accessory hemiazygos: left posterior superior thorax. The Respiratory System Chapter 24 p.752

A. Introduction 1. The cardiovascular system and the respiratory system cooperate in order to: i. supply oxygen which is required by cells to produce ATP ii. eliminate carbon dioxide which produces acidity that is toxic to cells 2. The respiratory system provides for gas exchange, intake of oxygen and elimination of carbon dioxide, whereas the cardiovascular system transports these gases in the blood between the lungs and the body's cells. 3. Failure of either system results in rapid death due to oxygen starvation and accumulation of waste molecules. 4. In addition to functioning in gas exchange, the respiratory system also: i. regulates blood pH ii. contains receptors for smell iii. filters inspired air iv. produces sound v. eliminates some water vapor and heat in exhaled air B. Respiratory System Anatomy 1. The upper respiratory system includes: i. nose ii. pharynx iii. structures associated with the above two 2. The lower respiratory system includes: i. larynx ii. trachea iii. bronchi iv. lungs 3. Functionally, the respiratory system consists of two portions: i. conducting zone, which includes the structures that filter, warm, and moisten air, and conduct air into the lungs: a. nose b. pharynx c. larynx d. trachea e. bronchi f. broncholies

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g. terminal bronchioles ii. respiratory zone, which consists of those structures where gas exchange occurs: a. respiratory bronchioles b. alveolar ducts c. alveolar sacs d. alveoli 4. Nose: i. The nose consists of two major portions: a. external nose, which consists of a bony framework (fromed by the frontal bone, nasal bones, and maxillae), flexible hyaline cartilage; two openings called the external nares or nostrils which lead into small cavities called the nasal vestibules b. internal nose, - anteriorly, it merges with the external nose - posteriorly, it communicates with the pharynx via two internal nares (choanae) - its walls have openings for ducts from the paranasal sinuses and the nasolacrimal ducts Air flows through the nose as follows: a. air enters the nostrils and is filtered by course hairs that line the nasal vestibules b. air then whirls through the superior, middle, and inferior meatuses c. air comes into contact with the olfactory epithelium d. air is warmed by blood in capillaries e. air is moistened by mucus secreted by goblet cells f. air is cleansed as mucus traps dust particles; the cilia move the dustladen mucus toward the pharynx iv. The interior structures of the nose therefore perform the following major functions: 1. incoming air is warmed, moistened, and filtered 2. olfactory stimuli are detected 3. large, hollow resonating chambers modify speech sounds 5. Pharynx: i. The pharynx or throat is a funnel-shaped tube that is located anterior to cervical vertebrae, posterior to the nasal and oral cavities, and superior to the larynx; its wall is composed of skeletal muscles and is lined with mucous membrane. ii. The pharynx functions as a passageway for air and food, provides a resonating chamber for speech sounds, and houses the tonsils. iii. The pharynx consists of three major portions: a. superior nasopharynx: - extends from the internal nares to the plane of the soft palate - its wall has openings for the internal nares and the auditory or pharyngotympanic (or eustachian) tubes (with which the pharynx exchanges small volumes of air)

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- the posterior wall contains the pharyngeal tonsil (or adenoid) b. intermediate oropharynx: - extends from the soft palate to the level of the hyoid bone - it communicates with the mouth via the fauces - it is a common passageway for air, food, and drink - its wall contains the pairs of palatine and lingual tonsils c. inferior laryngopharynx or hypopharynx: - extends from the level of the hyoid bone downward to the esophagus posteriorly and the larynx anteriorly - it is both a respiratory and digestive passageway 6. Larynx: i. The larynx or voice box is a short passageway that extends from the laryngopharynx to the trachea, anterior to C4-C6. ii. The wall of the larynx contains nine pieces of cartilage: a. thyroid cartilage (Adam's apple) is composed of two fused plates of hyaline cartilage that form the anterior wall of the larynx - it is usually larger in males than in females - it is connected to the hyoid bone by the thyrohyoid membrane b. epiglottis is a large leaf-shaped piece of elastic cartilage whose stem is attached to the anterior rim of the thyroid cartilage and hyoid bone - during swallowing, elevation of the larynx causes the free edge of the epiglottis to close the glottis and thus prevent food and liquids from entering the rima glottidis c. cricoid cartilage is a ring of hyaline cartilage that forms the inferior wall of the larynx d. two arytenoid cartilages are triangular pieces of mostly hyaline cartilage located at the posterior, superior border of the cricoid cartilage - they are involved in moving the vocal folds e. two corniculate cartilages f. two cuneiform cartilages iii. The inner lining of most of the larynx is a ciliated mucous membrane whose cilia move dust-laden mucus upward toward the pharynx. iv. The mucous membrane is arranged to form two pairs of folds: a. upper ventricular folds (false vocal cords) which can come together to close the space between them called the rima vestibuli b. lower vocal folds (true vocal cords) which can vibrate in response to air flow to produce sound waves - the greater the pressure of air, the louder the sound - pitch is controlled by the tension on the vocal folds; the greater the tension, the higher the pitch (and vice-versa) 7. Trachea: i. The trachea or windpipe is a tube located anterior to the esophagus and extends from the larynx down to the superior border of the fifth thoracic vertebra where it divides into right and left primary bronchi.

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ii. The wall has an inner lining that is a ciliated mucosa which moves dust-laden mucus up toward the pharynx. iii. The wall contains a stack of 16 to 20 C-shaped pieces of hyaline cartilage whose open sides face the esophagus - these incomplete rings of cartilage permit slight expansion of the esophagus into the trachea during swallowing and also provide a semirigid support to prevent inward collapse of the tracheal wall 8. Bronchi: i. At the superior border of the fifth thoracic vertebra, the trachea divides into the right primary bronchus, which enters the right lung, and the left primary bronchus, which enters the left lung; a. the right primary bronchus is more vertical, shorter, and wider than the left one b. the primary bronchi contain C-shaped pieces of cartilage and are lined by a ciliated mucosa ii. At the point where the trachea divides into the right and left primary bronchi, there is an internal ridge called the carina iii. After entering the lungs, the primary bronchi divide into secondary (lobar) bronchi, three in the right lung and two in the left lung. iv. The secondary bronchi branch into tertiary (segmental) bronchi which in turn divide into bronchioles. v. The bronchioles branch into progressively smaller and smaller bronchioles and eventually into terminal bronchioles. vi. This continuous branching from the trachea forms the bronchial tree. vii. Several changes are observed as branching progresses in the bronchial tree: a. the epithelium changes from ciliated to nonciliated in the terminal bronchioles b. C-shaped pieces of cartilage in the primary bronchi are gradually replaced by plates of cartilage that finally disappear in the distal bronchioles c. as the cartilage decreases, the amount of smooth muscle tissue increases

- smooth muscle encircles the lumen in spiral bands and its contraction is affected by the ANS and by various chemicals

9. Lungs: i. The lungs are paired cone-shaped organs located in the thoracic cavity. ii. Separating the two lungs are the heart and other structures in the mediastinum. iii. The lungs are individually enclosed and protected by the pleural membrane which consists of two layers: a. superficial parietal pleura which is attached to the thoracic wall b. deeper visceral pleura which is attached to the lungs - between the pleurae is the parietal cavity which contains a lubricating fluid secreted by the membranes; inflammation of the pleural membrane, called pleurisy or pleuritis, may cause pain due to friction between the two layers of the pleural membrane iv. Gross anatomy: a. the lungs extend from the diaphragm to just slightly above the clavicles and lie against the ribs anteriorly and posteriorly

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b. the broad inferior portion of a lung is the base, and the narrow superior portion is the apex c. the costal surface of a lung lies against the ribs d. the mediastinal (medial) surface of a lung contains a region, the hilus, through which bronchi, pulmonary blood vessels, lymphatic vessels, and nerves enter and exit the lung - these structures are held together by the pleura and connective tissue, and form the root of the lung e. on its medial surface, the left lung has the concave cardiac notch which the heart rests against v. Lobes and Fissures: a. In the left lung, the oblique fissure separates the superior lobe from the inferior lobe. b. In the right lung, the upper part of the oblique fissure separates the superior lobe from the inferior lobe, whereas the lower part of the oblique fissure separates the inferior lobe from the middle lobe; the horizontal fissure of the right lung subdivides the superior lobe to form the middle lobe. c. Each lobe receives its own secondary (lobar) bronchus - the right primary bronchus divides into the superior, middle, and inferior secondary (lobar) bronchi - the left primary bronchus divides into the superior and inferior secondary (lobar) bronchi d. In each lung, the secondary bronchi branch into 10 tertiary (segmental) bronchi that supply air to the bronchopulmonary segments of the lung. vi. Lobules and Alveoli: a. Each bronchopulmonary segment has many small compartments called lobules. b. Each lobule is wrapped in elastic connective tissue and contains a lymphatic vessel, an arteriole, a venule, and a branch of a terminal bronchiole called a respiratory bronchiole; a respiratory bronchiole subdivides into several alveolar ducts. c. Around the circumference of the alveolar ducts are numerous alveoli and alveolar sacs: - an alveolus is a cup-shaped outpouching lined by simple squamous epithelium and supported by a thin elastic basement membrane - alveolar sacs are two or more alveoli that share a common opening d. The alveolar walls consist of two types of alveolar epithelial cells: 1. type I alveolar are simple squamous epithelial cells that form a mostly continuous lining of the alveolar wall where gas exchange occurs 2. type II alveolar (septal) cells that secrete alveolar fluid which keeps the alveolar cells moist; alveolar fluid contains

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surfactant which lowers the surface tension of alveolar fluid to prevent collapse of the alveoli e. Associated with the alveolar wall are alveolar macrophages (dust cells) which are wandering phagocytes that remove dust and other debris in the alveolar spaces. f. The exchange of respiratory gases between the air spaces in the lungs and the blood occurs by diffusion across the respiratory membrane; this membrane consists of four layers: 1. a layer of type I and type II alveolar cells with wandering alveolar macrophages that constitutes the alveolar wall 2. an epithelial basement membrane underneath the alveolar wall 3. a capillary basement membrane that is often fused to the epithelial basement membrane 4. the endothelial cells of the capillary g. The respiratory membrane averages only 0.5 micrometers in thickness and it is estimated that the lungs contain about 300 million alveoli; therefore, there is an immense, extremely thin surface that permits rapid diffusion of significant volumes of the respiratory gases. vii. Blood and Nerve Supply to the Lungs: a. The lungs have a double blood supply. b. Deoxygenated blood is delivered to the lungs by the right and left pulmonary arteries; oxygenated blood drains into the right and left superior and inferior pulmonary veins. c. Oxygenated blood is delivered to the bronchi and bronchioles of the lungs by the bronchial arteries. C. Mechanics of Pulmonary Ventilation (Breathing) 1. The exchange of gases between the atmosphere, blood, and cells is called respiration; it consists of three major processes: i. pulmonary ventilation or breathing, which includes inspiration and expiration of air between the lungs and the atmosphere ii. external (pulmonary) respiration, the exchange of gases between the air spaces in the lungs and the blood in pulmonary capillaries; the blood gains O2 and loses CO2 iii. internal (tissue) respiration, the exchange of gases between the blood in systemic capillaries and the body's cells; the blood loses O2 and gains CO2 2. Inhalation: i. Inhalation (inspiration) is the process of moving air into the lungs. ii. It occurs when air pressure within the alveoli of the lungs, called alveolar pressure, is lower than atmospheric pressure. iii. It is achieved by expanding the lungs, a process which increases the volume of the lungs and therefore decreases the air pressure within the lungs below atmospheric pressure. iv. The major inspiratory muscles are: a. diaphragm (the most important inspiratory muscle) b. external intercostals

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- contraction of these muscles increases the volume of the thoracic cavity - this causes a decrease in the intrapleural pressure which in turn pulls the walls of the lungs outward v. The increase in volume of the lungs causes a decrease in alveolar pressure. vi. Therefore, air rushes down the pressure gradient from the atmosphere into the lungs; inspiration ends when the pressure difference is eliminated. vii. Accessory muscles of inspiration (e.g., scalene muscles) participate during deep, forceful inspiration. 3. Exhalation: i. Exhalation (expiration) is the process of moving air out of the lungs. ii. It occurs when air pressure in the lungs is greater than atmospheric pressure. iii. Unlike inspiration, normal expiration is a passive process since no muscular contractions are involved. iv. It is achieved by relaxation of the inspiratory muscles; this results in a decrease in the volume of the thoracic cavity due to: a. recoil of elastic fibers that were stretched during inspiration b. inward pull of surface tension due to the film of alveolar fluid v. This causes a decrease in lung volume which in turn increases the alveolar pressure. vi. Therefore, air rushes down the pressure gradient from the alveoli into the atmosphere. vii Forced expiration involves the contractions of abdominal and internal intercostal muscles. D. Regulation of Respiration 1. Role of the Respiratory Center: i. The respiratory muscles are controlled automatically by the respiratory center located in the brain stem. ii. The respiratory center consists of a dispersed group of neurons that is functionally divided into three areas: a. medullary rhythmicity area is located in the medulla oblongata: - it controls the basic rhythm of respiration b. pneumotaxic area is located in the superior portion of the pons: - helps coordinate the transition between inspiration and expiration c. apneustic area is located in the inferior portion of the pons: - it also helps coordinate the transition between inspiration and expiration

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LABORATORY IDENTIFICATION Thorax I. Skeletal System A. Thoracic Vertebra (review) B. Sternum: manubrium, body, xiphoid process, suprasternal notch, sternal angle C. Ribs: type ­ true, false, and floating ribs Features ­ head, neck, tubercle, costal angle, costal groove, right vs. left D. Costal cartilage II. Musculature A. External intercostals, internal intercostals B. Diaphragm: central tendon, caval foramen, esophageal hiatus, aortic hiatus III. Innervation A. Somatic ­ intercostal nerves B. Autonomic ­ sympathetic trunk, greater splanchnic nerve, lesser splanchnic nerve IV. Circulation A. Arterial supply ­ thoracic aorta, intercostal artery, internal thoracic artery Venous drainage ­ internal thoracic vein, azygos vein, hemiazygos vein, accessory hemiazygos vein Respiratory System *Identify the following structures on Head/Neck sagittal model (figure Unit 6 - 11 ) I. Nasal cavities A. openings ­ nostrils B. vestibule C. septum ­ vomer, perpendicular plate of ethmoid (review) D. conchae ­ superior, middle, inferior II. Nasopharyx A. opening of auditory tube B. pharyngeal tonsil III. Hyoid - thyrohyoid membrane IV. Larynx A. cartilages - thyroid, cricoid, epiglottic, arytenoids B. vessels ­ superior thyroid artery C. muscles ­ cricothyroid, thyrohyoid D. folds - ventricular folds (false vocal cords), vocal fold (true vocal cord) V. Trachea VI. Bronchi: primary (right, left), secondary, tertiary VII. Lungs A. right - lobes (superior, middle, inferior), horizontal fissure, oblique fissure, hilum, root (bronchus, pulmonary artery, pulmonary vein)

B. left - (superior, inferior), oblique fissure, hilum, root (bronchus, pulmonary artery, pulmonary vein)

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ABDOMEN AND THE DIGESTIVE SYSTEM Abdomen Muscular System: p.341 Rectus abdominis External oblique Internal oblique Transversus abdominis Action: help contain and protect the abdominal viscera; flex, lateral flex, and rotate the vertebral column; compress abdomen Quadratus lumborum: Action: lateral flexion of vertebral column Circulation: From descending abdominal aorta: p.505 Parietal branches: 1. inferior phrenic ­ diaphragm 2. lumbar (4 pairs) ­ posterior abdominal wall 3. median sacral ­ pelvis Visceral branches: 3 Paired: 1. suprarenal ­ adrenal glands. 2. renal: kidney 3. gonadal ­ testicular, ovarian 3 unpaired: 1. celiac trunk has 3 branches: left gastric; common hepatic; splenic 2. superior mesenteric: small intestine to part of transverse colon 3. inferior mesenteric: Drainage: p.525 Inferior phrenic, hepatic, suprarenal, renal gonadal, and lumbar veins inferior vena cava Hepatic Portal Circulation: p.530 Detours venous blood from the GI organs and spleen through the liver before it returns to the heart. Hepatic portal vein is formed by the union of the superior mesenteric vein and splenic vein, which receive blood from inferior mesenteric vein. The liver is receiving nutrient-rich but deoxygenated blood via hepatic portal vein; it also is receiving oxygenated blood via hepatic artery, a branch of the celiac trunk. This mixed blood in sinusoids hepatic vein inferior vena cava. (Increased pressure in the hepatic portal vein causes ascites, accumulation of several liters of fluid in the peritoneal cavity; esophageal hemorrhage.)

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The Digestive System

chapter 25

p. 782

Digestion is the breaking down of larger food molecules into molecules that are small enough to enter body cells and absorption is the passage of these small molecules into blood and lymph; the organs that collectively perform these functions comprise the digestive system. Overview of the Digestive System 1. The organs of the digestive system are divided into two groups: i. gastrointestinal (GI) tract or alimentary canal, which is a tube that extends from the mouth to the anus through the ventral body cavity; it includes the following organs: a. mouth b. most of the pharynx c. esophagus d. stomach e. small intestine f. large intestine ii. accessory digestive organs, which include: a. teeth b. tongue c. salivary glands d. liver e. gallbladder f. pancreas 2. The digestive system performs six major activities: i. ingestion (eating) ii. secretion of water, acid, buffers, and digestive enzymes iii. mixing of food with secretions and propulsion of food along the GI tract, i.e., motility iv. digestion of food by both mechanical and chemical processes v. absorption of digested food molecules into the blood and lymph vi. defecation of wastes, indigestible substances, and bacteria in the form of feces 3. Mechanical digestion includes: i. chewing of food by the teeth before it is swallowed ii. churning of food by the smooth muscles of the stomach and small intestine so that it is thoroughly mixed with digestive enzymes 4. Chemical digestion is a series of catabolic reactions in which enzymes break down large food molecules, i.e., carbohydrates, lipids, protein, and nucleic acids, into smaller molecules that may be absorbed and used by body cells. C. Layers of the GI Tract 1. The wall of the GI tract, from the esophagus to the anal canal, consists of four major layers of tissue which, listed in sequence from innermost to outermost, are:

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i. mucosa, which is a mucous membrane that surrounds the lumen; it consists of three sublayers: a. inner lining layer of epithelium b. middle layer of areolar connective tissue called the lamina propria - contains most components of the mucosa-associated lymphoid tissue (MALT) c. outer layer of smooth muscle tissue called the muscularis mucosae ii. submucosa, which consists of areolar connective tissue a. it is highly vascular b. it contains a portion of the submucosal plexus (plexus of Meissner) which is a component of the enteric nervous system (ENS) iii. muscularis, which consists of muscle tissue a. in the mouth, pharynx, upper and middle parts of the esophagus, and the external anal sphincter, it consists of skeletal muscle tissue which produces voluntary swallowing and voluntary control of defecation b. throughout the rest of the GI tract, it consists of smooth muscle tissue that is generally divided into two sheets: - inner sheet of circular fibers - outer sheet of longitudinal fibers c. it contains the myenteric plexus (plexus of Auerbach) which is a component of the enteric nervous system (ENS); this plexus primarily controls GI tract motility iv. serosa, which is a serous membrane a. it is composed of areolar connective tissue covered by a layer of simple squamous epithelium; the esophagus lacks a serosa called the adventitia D. Peritoneum 1. Important features of the peritoneum include: i. The peritoneum is the largest serous membrane of the body and it consists of a layer of simple squamous epithelium with an underlying connective tissue. ii. The peritoneum consists of two layers: a. parietal peritoneum that lines the wall of the abdominopelvic cavity b. visceral peritoneum that covers some of the abdominal organs and constitutes their serosa - between the two layers is a slim space called the peritoneal cavity that contains serous fluid; accumulation of serous fluid in certain diseases is a condition called ascites iii. Some abdominal organs, e.g., kidneys and pancreas, are located on the posterior abdominal wall and are covered by peritoneum on their anterior surfaces only; these organs are said to be retroperitoneal. iv. The peritoneum contains large folds which: a. bind organs to each other and to the walls of the abdominal cavity b. contain blood vessels, lymphatic vessels, and nerves that supply the abdominal organs v. The folds of the peritoneum include: a. greater omentum

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- it is the largest peritoneal fold and contains large quantities of adipose tissue and many lymph nodes - it hangs like a fatty apron in front of the abdominal viscera, b. falciform ligament - it attaches the liver to the anterior abdominal wall and diaphragm c. lesser omentum, it suspends the stomach and duodenum from the liver and contains some lymph nodes d. mesentery, which extends from the posterior abdominal wall to wrap around the small intestine and then returns to is origin

- it attaches the small intestine to the posterior abdominal wall

e. mesocolon, which is an outward fold of the parietal peritoneum - it attaches the large intestine to the posterior abdominal wall Mouth (Oral Cavity or Buccal Cavity) Salivary Glands: i. Many small labial, buccal, palatal, and lingual glands in the mucous membrane secrete small amounts of saliva to keep the mouth and pharynx moist. ii. Three pairs of major salivary glands secrete major quantities of saliva when food enters the mouth: a. parotid glands b. submandibular glands c. sublingual glands iii. Saliva is 99.5% water and 0.5% solutes; notable solutes include: a. bacteriolytic lysozyme b. salivary amylase which initiates starch digestion c. lingual lipase which initiates triglyceride digestion F. Pharynx 1. Mastication or chewing reduces the food to a soft, flexible mass called a bolus that is swallowed. 2. In deglutition or swallowing, the bolus of food first enters the pharynx, 3. The pharynx is composed of skeletal muscle covered by mucous membrane. 4. Muscular contractions of the oropharynx and laryngopharynx help propel the bolus of food into the esophagus. G. Esophagus The esophagus is a muscular, collapsible tube that travels from the laryngopharynx down through the mediastinum anterior to the spine and posterior to the trachea, through the esophageal hiatus in the diaphragm, and ends in the superior portion of the stomach; 5. The esophagus performs two functions: i. secretes mucus ii. transports food to the stomach a. entry of food into the esophagus is regulated by the upper esophageal sphincter or UES. b. food is pushed through the esophagus by involuntary waves of muscular contraction called peristalsis, which is a function of the muscularis

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c. passage of the bolus is facilitated by mucus secreted by esophageal glands d. just above the diaphragm is the lower esophageal (gastroesophageal or cardiac) sphincter or LES which briefly relaxes to permit passage of the bolus from the esophagus into the stomach H. Stomach 1. The stomach is a typically J-shaped organ located directly under the diaphragm in the upper left portion of the abdominal cavity; its precise position and size vary continually. 2. The stomach consists of four major areas: i. cardia, which surrounds the superior opening of the stomach ii. fundus, which is the rounded portion above and to the left of the cardia iii. body, which is the large central portion iv. pylorus, which is the inferior portion that connects to the duodenum; it has two regions: a. pyloric antrum, which connects to the stomach's body b. pyloric canal, which leads into the duodenum 3. When the stomach is empty, its mucosa lies in large folds called rugae. 4. The pylorus communicates with the duodenum via the pyloric sphincter. 5. The concave medial border is called the lesser curvature; the convex lateral border is called the greater curvature. 8. Histology: i. the mucosa has surface mucous cells that secrete mucus c. the gastric glands contain four types of secretory cells: 1. mucous neck cells, which secrete mucus 2. chief (zymogenic) cells, which secrete pepsinogen and gastric lipase 3. parietal cells, which secrete hydrochloric acid (that converts pepsinogen into the active pepsin and kills microbes in food) and intrinsic factor (that is essential for absorption of vitamin B12) - the secretions of the above three types of cells collectively form gastric juice, which is secreted into the stomach lumen 4. G cells, which are located primarily in the pyloric antrum and secrete the hormone gastrin into the blood ii. submucosa iii. the muscularis has three layers of smooth muscle tissue: a. outer longitudinal layer b. middle circular layer c. inner oblique layer, found primarily in the body of the stomach iv. the serosa is called the visceral peritoneum 9. The functions of the stomach include: i. mixing waves that macerate food, mix it with gastric juice, and reduce it to a soupy liquid called chyme ii. propelling small quantities of chyme through the slightly open pyloric sphincter into the duodenum

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iii. digestion of proteins by pepsin into peptides; pepsin is secreted as inactive pepsinogen by chief cells and is subsequently converted into its active form by hydrochloric acid iv. limited digestion of triglycerides by gastric lipase v. the stomach usually empties all its contents into the duodenum about 2 to 4 hours after ingestion vi. the only substances absorbed into the stomach wall are: a. some water b. electrolytes c. certain drugs (notably aspirin) d. alcohol I. Pancreas 1. The pancreas is retroperitoneal and is located posterior to the greater curvature of the stomach. 2. The pancreas consists of three major regions: i. medial head located near the curve of the duodenum - projecting from the lower portion of the head is the hook-like uncinate process ii. central body located superior and to the left of the head iii. lateral, tapering tail 3. Pancreatic exocrine secretions pass from secretory cells into small ducts that unite to form two larger ducts: i. pancreatic duct (duct of Wirsung) a. in most people, it joins the common bile duct from the liver and gallbladder to form the hepatopancreatic ampulla (ampulla of Vater) which enters the duodenum at an elevation called the major duodenal papilla that is located about 10 cm below the pyloric sphincter ii. smaller accessory duct (duct of Santorini) that empties into the duodenum about 2.5 cm above the hepatopancreatic ampulla 6. Histology: i. about 1% of the glandular epithelial cells are organized into clusters called pancreatic islets (islets of Langerhans) a. they form the endocrine portion of the pancreas and secrete the following hormones which were studied in Chapter 23: - glucagon - insulin - somatostatin - pancreatic polypeptide ii. the remaining 99% of the glandular epithelial cells are arranged in clusters called acini a. they form the exocrine portion of the pancreas and secrete a mixture of fluid and digestive enzymes called pancreatic juice 7. Pancreatic juice: i. water ii. some salts

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iii sodium bicarbonate, which buffers acidic gastric juice in chyme, stops the action of pepsin, and provides the proper pH for the action of digestive enzymes in the small intestine iv. several digestive enzymes: a. pancreatic amylase, which digests carbohydrates b. trypsin, which digests proteins c. chymotrypsin, which also digests proteins d. carboxypeptidase, which also digests proteins e. elastase, which also digests protein f. pancreatic lipase, which digests triglycerides g. ribonuclease, which digests RNA h. deoxyribonuclease, which digests DNA J. Liver 1. The liver is the heaviest gland of the body and, after the skin, the second largest organ of the body; it is located under the diaphragm in the upper right portion of the abdominal cavity. 2. It is completely covered by a layer of dense irregular connective tissue that is, in turn, almost completely covered by visceral peritoneum. 3. The liver consists of two major lobes: i. large right lobe ii. smaller left lobe; associated with the left lobe are two smaller lobes: a. inferior quadrate lobe b. posterior caudate lobe - the right and left lobes are separated by the falciform ligament, in the free border of the falciform ligament is the ligamentum teres (round ligament), - the right and left coronary ligaments suspend the liver from the diaphragm 4. Histology: i. the lobes consist of functional units called lobules that are composed of specialized epithelial cells called hepatocytes (form plates as hepatic laminae) ii. some surfaces of the hepatocytes border on small bile ducts called bile canaliculi iii. other surfaces of the hepatocytes face vascular spaces called hepatic sinusoids whose blood drains into the central vein iv. the sinusoids are lined by endothelium and contain (in addition to blood) phagocytic cells called stellate reticuloendothelial (Kuppfer) cells which destroy worn-out leukocytes, erythrocytes, bacteria, and other foreign matter v. hepatocytes secrete bile into the bile canaliculi vi. a branch of the hepatic portal vein, a branch of the hepatic artery, and a bile duct typically accompany each other and collectively form a portal triad viii. bile canaliculi which converge to form larger ducts in the portal triads ix. these ducts merge to eventually form the larger right and left hepatic ducts, which unite to form the common hepatic duct that exits the liver x. the common hepatic duct merges with the cystic duct from the gallbladder to form the common bile duct which drains to the duodenum where it joins the

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pancreatic duct; bile enters the cystic duct and is temporarily stored in the gallbladder 5. The liver receives blood from two sources, and its blood drains into one set of veins: i. the hepatic artery provides oxygenated blood ii. the hepatic portal vein delivers deoxygenated blood containing newly absorbed nutrients from the GI tract - branches of these two blood vessels carry blood to the sinusoids, where oxygen, most nutrients and certain toxins are absorbed by the hepatocytes - products manufactured by hepatocytes and nutrients needed by other cells are secreted back into the blood, which then drains into the central vein and eventually into a hepatic vein 6. The nerve supply to the liver consists of parasympathetic innervation from the vagus (X) nerves and sympathetic innervation from the greater splanchnic nerves through the celiac ganglia. 7. In addition to secreting bile, the functions of the liver also include: i. carbohydrate metabolism ii. lipid metabolism iii. protein metabolism iv. processing of drugs and hormones v. excretion of bilirubin vi. synthesis of bile salts vii. storage of numerous substances including glycogen, certain vitamins, and some minerals viii. phagocytosis ix. activation of vitamin D K. Gallbladder 1. The gallbladder is a pear-shaped sac that is located in a depression of the inferior surface of the right lobe of the liver; it consists of a broad fundus, a central body, and a tapering neck. 3. The functions of the gallbladder are to store and concentrate bile until it is needed in the small intestine. 4. When the small intestine is empty, the sphincter of the hepatopancreatic ampulla or sphincter of Oddi closes; this causes bile to accumulate in the common bile duct and enter the cystic duct and the gallbladder where it is stored. 5. When food enters the duodenum, the hormone cholecystokinin (CCK) stimulates contraction of the wall of the gallbladder and relaxation of the sphincter of the hepatopancreatic ampulla; this causes bile to flow into the duodenum. 6. Bile partially an excretory product and partially a digestive secretion; bile has several important components including: a. bile salts play a role in emulsification of fats and absorption of the products of fat digestion b. cholesterol c. bile pigments, notably bilirubin that is derived from heme; one of the breakdown products of bilirubin gives feces their normal brown color L. Small Intestine

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1. The small intestine extends from the pyloric sphincter to the large intestine; it averages 2.5 cm in diameter and about 3 m in length in a living person, but is about 6.5 m long in a cadaver. 2. It consists of three regions: i. duodenum a. is about 25 cm long b. is retroperitoneal ii. jejunum a. is about 1 m long iii. ileum a. is about 2 m long b. meets the large intestine at the ileocecal sphincter 3. The small intestine receives blood from the superior mesenteric artery and the gastroduodenal artery; blood drains into the superior mesenteric vein. 5. Histology: Since almost all digestion and absorption of nutrients occurs in the small intestine, the standard four major layers that form the wall of the Gl tract have special modifications to ensure that these processes are completed in the small intestine: i. the mucosa has numerous villi which greatly increase the surface area available for digestion and absorption a. each villus has a core of lamina propria in which there are an arteriole, a venule, a capillary network, and a lacteal, i.e., a lymphatic capillary

ii. a. goblet cells which secrete mucus

absorptive cells which help digest and also absorb digested nutrients - the apical plasma membrane has numerous microvilli that form a brush border - the microvilli increase the surface area available for absorption - the brush border also contains several digestive enzymes v. the lamina propria contains areolar tissue and an abundance of mucosaassociated lymphoid tissue (MALT) vi. the submucosa of the duodenum contains duodenal (Brunner's) glands which secrete an alkaline mucus that helps neutralize gastric acid in the chyme vii. the mucosa and submucosa also have circular folds (or plicae circulares) which are permanent ridges that further increase the surface viii. the muscularis ix. the serosa 6. Functions: i. digestion of carbohydrates, proteins, and lipids is completed in the small intestine due to the collective action of pancreatic juice, bile, and intestinal juice ii. the surfaces of microvilli have brush-border enzymes: a. -dextrinase b. maltase c. sucrase d. lactase - the above four enzymes digest specific carbohydrates e. aminopeptidase f. dipeptidase

b.

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- these two peptidases digest proteins g. nucleosidases h. phosphatases - these two enzymes digest nucleotides iii. there are two types of movements that occur in the small intestine: a. segmentations slosh chyme back and forth to thoroughly mix the chyme with digestive juices and bring nutrients into contact with the mucosa for absorption b. a type of peristalsis called migrating motility complex (MMC) propels the chyme through the small intestine iv. about 90% of absorption of nutrients occurs in the small intestine (the other 10% occurs in the stomach and large intestine) a. absorbed nutrients pass from the absorptive cells into the capillary network or lacteal within a villus b. any undigested or unabsorbed substances pass into the large intestine M. Large Intestine 1. The functions of the large intestine include: i. completion of absorption ii. production of certain vitamins iii. formation and storage of feces iv. expulsion of feces 2. The large intestine is about 1.5 m long and 6.5 cm in diameter. 3. It is attached to the posterior abdominal wall by the mesocolon. 4. The large intestine consists of four major regions: i. cecum, a blind pouch in the lower right portion of the abdominal cavity a. chyme from the ileum enters the cecum via the ileocecal sphincter or valve b. attached to the cecum is the appendix or vermiform appendix ii. colon, which consists of four segments: a. retroperitoneal ascending colon ascends on the right side of the abdominal cavity to the right colic (hepatic) flexure b. transverse colon travels across to the left side to the left colic (splenic) flexure c. retroperitoneal descending colon descends on the left side of the abdominal cavity to the level of the iliac crest d. sigmoid colon travels medially from the left iliac crest to the level of the third sacral vertebra iii. rectum, which descends anterior to the sacrum and coccyx iv. anal canal, which is the terminal 2 to 3 cm of the rectum a. the mucous membrane is arranged in longitudinal folds called anal columns which contain blood vessels b. the opening to the exterior is called the anus which is normally closed by two sphincters: - internal anal sphincter of smooth muscle tissue (involuntary) - external anal sphincter of skeletal muscle tissue (voluntary)

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8. Functions: i. ileal peristalsis moves chyme through the ileocecal sphincter into the cecum ii. within the large intestine several types of movements occur: a. haustral churning b. peristalsis c. mass peristalsis iii. bacteria that live in the lumen perform several activities: a. ferment any remaining carbohydrates and release gases that contribute to flatus in the colon b. convert remaining proteins into amino acids and simpler substances, some of which contribute to the odor of feces c. decompose bilirubin to simpler pigments that give feces their brown color d. produce several vitamins including some B vitamins and vitamin K iv. due to absorption of water by epithelial cells, the chyme is converted into feces Note: Table 25.2 provides a Summary of Organs of the Digestive System and Their Functions.

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LABORATORY IDENTIFICATION Abdomen I. Musculature Anterior wall - external abdominal oblique internal abdominal oblique rectus abdominis (linea alba, tendinous intersections) transversus abdominis Posterior wall - quadratus lumborum, psoas major, illacus (review) II. Innervation: subcostal, iliohypogastric, ilioinguinal, III. Circulation A. Arterial supply From descending abdominal aorta: 1. Visceral paired branches: a. renal arteries b. gonadal arteries 2. Visceral unpaired branches: a. celiac trunk and its branches: left gastric, splenic, common hepatic b. superior mesenteric c. inferior mesenteric 3. Parietal branches: a. lumbar b. median sacral B. Venous Drainage 1. Inferior vena cava: a. renal veins b. hepatic vein 2. Hepatic portal vein a. superior mesenteric vein b. splenic vein ­ inferior mesenteric vein Digestive System I. Mouth Region ­ oral cavity, oral vestibule Palate ­ hard, soft (uvula) Tonsils ­ palatine tonsil, lingual tonsil Tongue II. Salivary glands: parotid, submandibular III. Oropharynx IV. Laryngopharynx * Some structures are shown on the sagittal section of the head/neck on figure Unit 6 ­ 11. V. Esophagus Teeth

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Tooth: crown, neck, root; dentin, enamel, cementum; pulp in pulp cavity, root canal, gingiva Types: incisor, cuspid (canine), premolar (first, second), molar (first, second, third) VI. Stomach 1. Regions: fundus, body, pyloris 2. Curvatures: greater curvature, lesser curvature 3. Muscles: cardiac sphincter (lower esophageal sphincter), pyloric sphincter 4. Folds: rugae VII. Small intestine 1. Duodenum: (major) duodenal papilla 2. Jejunum 3. Ileum: ileocecal sphincter (valve) 4. Circular folds (plicae circulares) VIII. Large intestine 1. Cecum - vermiform appendix 2. Colon - ascending, transverse, descending colon, sigmoid colon 3. Rectum, anal canal, anus 4. Flexures: right colic (hepatic) flexure, left colic (splenic) flexure 5. Features: haustra, teniae coli. IX. Liver 1. Lobes: right, left, caudate, quadrate 2. Gallbladder - cystic duct 3. Billiary system: hepatic ducts (right, left), common hepatic duct, common bile duct 4. Vessels: hepatic artery, hepatic portal vein, hepatic vein, inferior vena cava 5. Falciform ligament, ligamentum teres (round ligament) X. Pancreas 1. Head, body, tail 2. Pancreatic duct XI. Visceral Peritoneum 1. Greater omentum 2. Mesentery 3. Mesocolon

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PELVIC REGION ­ THE URINARY AND REPRODUCTIVE SYSTEMS Pelvis True and False Pelves p.235 The portion of the bony pelvis superior to the pelvic brim is the false (greater) pelvis. Inferior to the pelvis brim is the true (lesser) pelvis, which surrounds the pelvic cavity. Comparison of Female and Male Pelves Female General structure Light and thin False pelvis Shallow Pelvic brim (inlet) Large and more oval Obturator foramen Oval Pubic arch > 90 degree angle Pelvic outlet Wider The Urinary System p. 186 Male Heavy and thick Deep Smaller and heart-shaped Round < 90 degree angle Narrower Chapter 26 p.821

Internal anatomy of the kidneys Renal cortex Renal medulla, which contains renal pyramids and renal columns The nephrons are the functional units of the kidney.

Each nephron: Consists of a renal corpuscle, where plasma is filtered, and a renal tubule into which the filtered fluid passes. Renal corpuscle = Glomerulus + Bowman's capsule: filtration Renal tubule = Reabsorption and secretion Proximal (Convoluted) Tubule (PCT) ­ has microvilli as brush border, uncontrolled reabsorption and secretion. Loop of Henle ­ establishes an osmotic gradient in the renal medulla. Distal (Convoluted) Tubule (DCT) ­ variable controlled reabsorption of Na+ and H2O and secretion of K+ and H+; Vascular component: p.827 Path of blood flow: Renal artery segmental a. interlobar a. arcuate a. (arch between medulla and cortex) interlobular a. afferent arterioles glomerulus efferent arterioles peritubular capillaries interlobular v. arcuate v. interlobar v. renal vein Afferent arteriole ­ carries blood to glomerulus Glomerulus ­ a tuft of capillaries (filter) Efferent arteriole ­ drains blood out of glomerulus, then divide to form Peritubular capillaries ­ supply the renal tissue; take up the substances that are reabsorbed by the tubules, supply substances that are secreted by the tubules.

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Urine drainage: Bowman's capsule (collects the glomerular filtrate) PCT Descending limb of the loop of Henle Ascending limb DCT Collecting duct (not part of nephron) minor calyx major calyx the renal pelvis Outside of the kidneys Ureters Urinary bladder Urethra Two types of nephrons: Cortical nephrons: 80%; glomeruli lie in the outer layer of cortex; Loop of Henle: short, dips only slightly into the medulla. Juxtamedullary nephrons: fewer; glomeruli lie in the inner layer of cortex; Loop of Henle: long, plunges through the entire depth of the medulla; peritubular capillaries form vasa recta

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Reproductive System Male

Chapter 27

p.846

Scrotum: Supporting sac for the testes. Testis: produce sperm and the male sex hormone Lobules containing one to three seminiferous tubules, where sperm are produced Spermatogenic cells: cells at any of the sperm-forming stages. Sertoli cells: large, extend from the basement membrane to the lumen of the tubule. Forming blood-testis barrier, support and protect developing spermatogenic cell. Leydig cells (interstitial cells): in the space between adjacent seminiferous tubules; secreting testosterone. Reproductive System Ducts in Males Functions: transport, store, and assist in maturation of sperm. Ducts of the Testis: rete testis (a network of ducts) Epididymis: efferent ducts ductus epididymis; sperm been stored and increases motility. Ductus (vas) deferens: stores sperm Ejaculatory ducts: union of the duct from the seminal vesicle and the ductus deferens. Urethra Accessory Sex Glands: secrete most of the liquid portion of semen. Seminal Vesicles Prostate Gland Bulbourethral Glands Penis p. 859 ­ corpus cavernosum, corpus spongiosum, glans penis, prepuce (foreskin), urethra Spermatozoon ­ head (acrosome, nucleus), Tail: neck, middle piece, principal piece, end piece

P.852

Female Ovaries: p.860 Are paired female gonads Produce secondary oocytes and hormones: progesterone, estrogens, inhibin, and relaxin. Cortex: consists of ovarian follicles: oocyte with surrounding follicular cells (a single layer) or granulosa cells (later, several layers). Corpus luteum: contains the remnants of an ovulated mature follicle. Corpus albicans: fibrous tissue. Medulla: Uterine (fallopian) tubes: Transport a secondary oocyte, sites of fertilization. Fimbriae: a fringe of fingerlike projections. Uterus:

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Site of menstruation, implantation of a fertilized ovum, development of the fetus, and labor Regions: body, fundus, cervix Layers: endometrium, myometrium, perimetrium Ligaments: broad ligament Vagina: Vulva: refers to the external genitals of the female. clitoris labia majora labia minora Perineum Is the diamond-shaped area medial to the thighs and buttocks of both males and females. A line between the ischial tuberosities divides the perineum into An anterior urogenital triangle that contains the external genitalia and A posterior anal triangle that contains the anus.

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LABORATORY IDENTIFICATION I. Skeletal System A. Hip bone (coxal bone, os coax) ­ review B. Sacrum Anterior: a. base c. sacral promontory Posterior: e. sacral hiatus g. posterior sacral foramen C. Coccyx D. Joints ­ pubic symphysis, sacro-iliac joint C. True and False Pelves a. false (greater) pelvis c. pelvic brim e. pubic arch

b. sacral ala d. anterior sacral foramen f. median sacral crest h. sacral cornu

b. true (lesser) pelvis d. arcuate line f. pubic symphysis

II. Urinary System A. Organs: kidney, ureter, urinary bladder, urethra B. Kidney Renal capsule Renal cortex Renal medulla - renal pyramids and renal columns Renal artery and renal vein Minor calyx major calyx renal pelvis Microscopic structures: Afferent arteriole Efferent arteriole Nephon a. renal corpuscle ­ glomerulus + Bowman's capsule b. renal tubule - Proximal Convoluted Tubule (PCT) Loop of Henle Distal Convoluted Tubule (DCT) Collecting duct

III. Reproductive System Male A. Scrotum, Testis B. Male reproductive ducts: 1. Epididymis 2. Ductus (vas) deferens 3. Ejaculatory duct 4. Urethra

C. Accessory Sex Glands

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1. Seminal Vesicles 2. Prostate Gland 3. Bulbourethral Glands D. Penis: 1. Corpora cavernosa penis 2. corpus spongiosum penis 3. glans penis 4. prepuce (foreskin) E. Spermatozoon ­ head (acrosome, nucleus), middle piece, tail Female A. Ovary B. Uterine tube (Fallopian tube or oviduct) - fimbriae C. Uterus 1. Regions - fundus, body, cervix 2. Layers - endometrium, myometrium 3. Ligament - round D. Vagina E. Vulva: 1. Labia majora (singular term: labium majus) 2. Labia minora (singular term: labium minus) 3. Clitoris

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APPENDIX A ORAL LABORATORY IDENTIFICATION AREAS ­ STRUCTURES Student Name __________________________ Section ___________

Description ­ The following areas may be used to complete the ORAL LABORATORY IDENTIFICATION. Each area (except the cranial nerve exits) is worth 5 points. A minimum of 60 points is required, and a maximum of 100 points may be completed. Procedure ­ Correctly identifies and pronounces all of the structure for a designated area either to the instructor, assigned tutor, or to a student-teacher (Signed off by the instructor or tutor). The instructor or student-teacher will initial and indicate the date of completion for each area. AREA INITIALS DATE 1. Integumentary System ­ Skin Model _________ ______ 2.Skeletal System ­ Osteon Model _________ ______ 3. Skeletal System ­ Bones _________ ______ 4. Nervous System ­ Neuron Model _________ ______ 5. Muscular System ­ Muscle Fiber Model _________ ______ 6. Circulatory System ­ Heart model _________ ______ 7. Circulatory System ­ Major Arteries & Veins _________ ______ 8. Back Region ­ Spinal Cord Models _________ ______ 9. Upper Limb Region ­ Skeletal (1-3) _________ ______ 10. Upper Limb Region ­ Skeletal (4-8) _________ ______ 11. Upper Limb Region ­ Muscles (model) _________ ______ 12. Upper Limb Region ­ Muscles (cadaver) _________ ______ 13. Upper Limb Region ­Vessels, Nerves & Joints (model) _________ ______ 14. Lower Limb Region ­ Skeletal (1-3) _________ ______ 15. Lower Limb Region ­ Skeletal (4-8) _________ ______ 16. Lower Limb Region ­ Muscles (model) _________ ______ 17. Lower Limb Region ­ Muscles (cadaver) _________ ______ 18. Lower Limb Region ­ Vessels, Nerves & Joints (model) _________ ______ 19. Head & Neck Region ­ Skull (1-3) _________ ______ 20. Head & Neck Region ­ Skull (4-5) _________ ______ 21. Head & Neck Region ­ Facial Bones & Fetal Skull _________ ______ 22. Head & Neck Region ­ Muscles (model) _________ ______ 23. Head & Neck Region ­ Vessels, Ventricle, Meninges _________ ______ 24. Head & Neck Regions ­ Brain Model _________ ______ 25. Respiratory System _________ ______ 26. Digestive System _________ ______ 27. Urinary System _________ ______ 28. Reproductive System _________ ______ 29. Thorax & Abdomen ­ Muscles & Vessels _________ ______ 30. Cranial Nerves and their exit (10 points) ­ Instructor _________ ______ Total Points __________________

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APPENDIX B CADAVER CARE Human cadavers at Triton College are viewed by Professors and Students as Our Teachers. We realize that these individuals volunteered their physical beings so we could better understand the design of the human body. I. Cadaver Room (S 323) ­ The cadaver room should be locked when not in use. Individuals and students other than those taking human anatomy and physiology courses should get permission from a human anatomy and physiology instructor prior to viewing the cadavers. II. Cadaver Care ­ All human anatomy students are responsible for the proper care of our human cadavers when in the cadaver room. Moistened ­ Cadavers need to be periodically moistened with the spray bottle, which contain water to prevent drying out. Covered ­ After studying the cadavers, each cadaver must be covered with moist towels prior leaving the cadaver room. Identification ­ Under NO circumstances should the IDENTIFICATION TAG on the leg or wrist of a cadaver or attached to the zipper be removed. The cremains cannot be properly identified and return to the family without these identification tags. Structures ­ Do not pull on muscles, tendons, blood vessels, or nerves. These structures are often fragile and are easily damaged. III. Preservation Fluids ­ The chemical contents of fluid used in cadaver preservation are posted on the wall in the cadaver room. PREGNANT WOMEN should consult with their physician prior to working with the cadavers. Any students allergic or sensitive to fluids used in cadaver preservation should notify your instructor. IV. Cadaver Dissection ­ Cadaver dissection guides can be downloaded from the website: www.triton.edu/faculty/bjiang. Student should contact the instructor regarding any questions about the guides PRIOR TO DISSECTING structures. No structures should be dissected without proper authorization from your instructor.

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APPENDIX C GRADE PORTFOLIO Tests Possible Points Actual Points Total Possible Points Total Actual Points % Date, Comments

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AN INTRODUCTION TO THE HUMAN BODY

134 pages

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