BIO 312 Study Guide (2014-15 Maher) - Instructor Maher at University Of Wisconsin - La Crosse - StudyBlue Good to have you back! If you've signed in to StudyBlue with Facebook in the past, please do that again. BIO 312 Study Guide (2014-15 Maher) BIO 312 Study Guide (2014-15 Maher) StudyBlue Simple Squamous Epithelium Fxn: diffusion & filtration Location: lining of ventral cavity, heart, blood vessels, internal organs (endothelium). kidney (glomerular capsue). aleovli (air sacs) Simple Cuboidal Epithelium Location: glands, ducts, kidney tubules Advertisement ) Simple Columnar Epithelium Fnx: secretion & absorption (goblet cells - special columnar cells that secrete mucus along lumen of intestines & trachea) Location: lumen of digestive tract, gallbladder, uterine (fallopian) tubes, collecting ducts of kidneys Pseudostratified Columnar Epithelium Location: lumen of nasal cavity, trachea, & bronchi.

portions of male reproductive tract Stratified Squamous Epithelium Location: epidermis of skin. lining of mouth, pharynx, esophagus, rectum, anus, vagina. Loose (Areolar) CT Fxn: wraps & cushions organs, connects epithelium to underlying tissues (under basal membrane) Location: beneath epithelium (lamina propria), surrounding organs & capillaries Dense Regular CT Location: tendons, aponeuroses (muscle sheath), ligaments Dense Irregular CT Location: joint capsules, dermis of skin, submucosa (beneath mucus membrane) of digestive tract Adipose Tissue Location: hypodermis. surrounds kidneys, eyes, other organs. breast tissue.

basal cell carcinoma -small shiny bump with pearly edges squamous cell carcinoma -metastasize to lymph nodes if untreated -raised, red, scaly -found on scalp, ears, lower lip, back of hand malignant melanoma -origin: melanocytes of pre-existing mole -most deadly -metastasizes quickly, drug resistant, early detection is crucial - sensory neurons - conduct sensory info from PNS to CNS - cell body located in dorsal root ganglia Advertisement - uncommon/special; located in eye, ear, nose - aka motor neurons - can also be interneurons (build bridge between sensory & motor neurons) - located in ventral & lateral horns of spinal cord (CNS) tests ability to differentiate between two points on skin being stimulated simultaneously Circumduction no blood vessels within tissue basement (basal) membrane forms border between epithelium and loose CT (lamina propria) cell -hair-like organelles on cell surface that move liquids (ie. mucus) -found on apical surface of pseudostratifed columnar epithelium.

squamous simple squamous epithelium lining heart, blood vessels, and ventral body cavity histology groups of cells similar in structure, function, and embryonic origins anatomy Studies the structure of the body parts and their relationships to one another physiology study of body function Physiology Studies the function of the body: how the body parts work and carry out their life-sustaining activities standard anatomical position -used when applying anatomical & directional terms -standing with feet flat and palms facing inwards body cavities internal chambers that house organs (dorsal & ventral) section of ventral cavity containing heart & lungs abdominal cavity urinary bladder, reproductive organs, distal portions of digestive tract longitudinal sections cut structure along long axis (ex. blood vessel looks like "l") cross-sections cut structure perpendicular to long axis (ex. blood vessel looks like "o") organ structure composed of two or more types of tissue that perform a specific function in body organ system group of organs acting together to perform specific body function surface anatomy external landmarks that provide road map for location of internal structures palpation feeling body surface with hands (ex.

locating artery in wrist to take pulse) connective tissues perform a variety of functions: binding, support, insulation, transportation mesenchyme embryonic tissue that gives rise to connective tissues matrix; matrices non-living, acellular network of cells, fibers, and ground substance fibers provide support network in CT association fibers (intra) Name the 3 major connection fiber types that allow cerebral hemisphere communication ground substance amorphous (unstructured) gel-like substance surrounding cells 4 classes of connective tissue: 1. connective tissue proper -type of cell found in CT proper -makes up extracellular matrix & produces collagen Fibroblast the cells type of connective tissue proper Three types of fibers: 1. Collagen fibers - thick, light-stained strands; provide tensile strength 2. Elastic fibers - thin, dark-stained strands; provide resiliency 3.

Reticular fibers - form framework that stabilizes/supports many organs (can't be seen) adipocytes -cells of adipose tissue that store fat in large vacuole in center of cell -nucleus pushed off to side -do not form ground substance or fibers epithelium; epithelia tissue composed of tightly bound cells that cover/line external & internal body surfaces and form glands 4 major classes of tissue: 1.

epithelial tissue skin; tough coating that covers the entire body surface Fnx: protection, temp regulation, sensory perception, storage, synthesis, excretion keratinized stratified squamous epithelium cells of epidermis that produce keratin (fibrous protein) melanocytes cells in epidermis that produce melanin (pigment; protects from UV radiation) thick skin -five strata (includes stratum lucidum) -thick stratum corneum -covers rest of body & has hair stratum corneum -15-30 layers of dead keratinized cells (no nucleus) Fnx: protects underlying cells, minimize water loss Stratum corneum outermost layer of both thick and thin skin; consists of 15-20 layers of dead keratinized cells; protects the underlying cells and helps to minimize water loss from the body stratum lucidum -translucent layer found only in thick skin -stained darker in lab translucent layer immediately deep to s.

corneum; FOUND ONLY IN THICK SKIN stratum granulosum -3 to 5 cell layers with a granulated appearance -keratin formation begins in this layer and cells begin to die Stratum granulosum 3-5 cell layers thick; KERATIN FORMATION BEGINS IN THIS LAYER AND CELLS BEGIN TO DIE (dark purple) stratum spinosum -cells shrink when prepared on slide giving them a spiny appearance stratum basale (germinativum) -single layer of cells superficial to dermis -mitotically active; rapidly replace cells being shed by stratum corneum -takes 15-30 days for cells form stratum basale to move to stratum corneum Stratum Basale (germinativum) deepest layer of the epidermis; single layer of cells located adjacent to the dermis; mitotically active, RAPIDLY REPLACING CELLS OF S.

CORNEUM THAT ARE CONSTANTLY BEING SHED dermis (corium) -composed mainly of connective tissue and accessory structures Dermis (corium) consists of connective tissue, hair follicles, exocrine glands, somatosensory receptors, and blood and lymphatic vessels papillary layer -loose (areolar CT), tiny blood vessels, somatosensory receptors (tactile corpuscles) tactile corpuscles -most numerous in sensitive areas of skin (lips, fingertips, eyelids) tactile corpuscle -composed of adipose tissue and loose (areolar) CT Fnx: connects skin to underlying tissues (technically not skin itself) stores fat, insulates -aka: superficial fascia (pl-fasciae), subcutaneous layer Hypodermis serves to attach the skin to the underlying tissues of the body and provides insulation Hypodermis lies deep to the reticular layer of the dermis; composed primarily of adipose tissue and areolar (loose) connective tissue; serves to connect the skin to underlying tissues, acts as an insulator and serves as a fat storage depot sweat (sudoriferous) glands -produce watery secretion that helps cool body, secretes waste -2 types

: eccrine (merocrine) & apocrine eccrine (merocrine) sweat glands -ducts found in skin all over body -most numerous in hands, feet, forehead apocrine sweat glands -secrete into hair follicles a protein/fatty substance that is digested by bacteria, hence, BO -only found in anogenital (anal) and axillary regions hair non-living structure composed of the protein keratin that is produced in hair follicles shaft of hair extends above surface of skin Shaft (of the hair) the part of the hair that extends above the surface of the skin root of hair the portion of had that is located in the epidermis and dermis hair bulb expanded end of the root arrector pili muscle smooth muscle that causes hair to stand up when it contracts sebaceous glands secrete sebum into the follicle Sebaceous glands secrete an oily substance called sebum into a hair follicle (sebum protects and lubricated the hair and inhibits the growth of bacteria) sebum oily substance that protects & lubricates hair; inhibits growth of bacteria nails -protect tips of the fingers and toes -similar in structure to hair -quick way to identify percent body surface area affected by burns (=>prioritize

 burn victims) -does not apply to children The Rules of Nines a quick method of estimating the percent of bod surface area affected by burns; knowing this, medical personnel can quickly asses the severity of a burn and thereby increase the chances of survival first degree burn -only surface of epidermis damaged (partial-thickness burn) -inflammation of damaged tissues -heals in a week, no scars ex.) sunburn -epidermis & often part of dermis damaged (partial-thickness burn) -blistering, pain, swelling - healing occurs from accessory structures & edge of burn -heals in 2 weeks (epidermis only)-2 months (dermis) and scars third degree burn -epidermis & dermis destroyed; hypodermis and tissues beneath damaged (full-thickness burn) -painless due to nerve destruction -blood vessels & accessory structures destroyed => cannot heal and requires skin graft -infection likely, life threatening Elevation Epithelium A tissue composed of tightly bound cells that covers/lines all external and internal body surfaces and forms glands Simple Squamous Epithelium (in kidney) Simple Squamous Epithelium (in lungs) Simple Cuboidal Epithelium (in kidney) Simple

 Columnar Epithelium (in jejunum) Simple Columnar Epithelium (in duodenum) Stratified Squamous Epithelium (in esophagus) Sagital plane divides the body into left and right pieces Frontal plane Divides the body into dorsal and ventral (front and rear) Transverse plane (cross-section) divides the body into superior and inferior parts (top and bottom) Simple Squamous Epithelium- description, function, and location -Description: single layer of flat, scale-like cells -Function: diffusion and filtration -Location:lining of the ventral body cavity, heart & blood vessels, kidney, covering all internal organs, alveoli (air sacs) of lungs Simple Cuboidal Epithelium- description, function, location -Description: single layer of cube-shaped cells with round, dark-stained nuclei located in center of cell -Function: secretion and absorption -Location: glands, ducts, and kidney tubules Simple Columnar Epithelium- description, function, and location -Description: single layer of rectangular cells with oval shaped nuclei located at basal end of cell -Function: secretion and absorption (of nutrients and water) -Location: lining of digestive tract, gall

bladder, uterine tubes and collecting ducts of kidney Pseudostratified Columnar Epithelium- description, function, and location -Description: single layer of cells, which appear stratified die to their varying heights and nuclei location; may have cilia covering apical surface -Function: protection and secretion -Location: lining of nasal cavity, trachea, bronchi, and portions of the male reproductive tract Stratified Squamous Epithelium- description, function and location -Description: multiple layers of cells, only the deepest layer contacts the basement membrane -Function: protection -Location: epidermis of skin, lining of mouth, pharynx, esophagus, rectum, anus and vagina 4 main types of connective tissues 1) connective tissue proper 1) Matrix (ground substance + cells/fibers) 2) Ground substance (material between cells/fibers) 3) Fibers (collagen elastic, reticular) 4) Cells thick, light-staining strands; provide tensile strength Elastic fibers thin, dark-staining strands (resemble hairs); provide resilency Reticular fibers form framework to help stabilize and support many organs Pseudostratified Columnar Epith

elium (in trachea) Loose (Areolar) Connective Tissue-Description, Function and Location -Description: semi-fluid ground substance containing collagen and elastic fibers loosely arranged around fibroblasts and other cells -Function: wraps and cushions organs, connects epithelium to underlying tissues -Location: most widespread type of connective tissue in the body; found beneath epithelium(lamina propria), surrounding organs and capillaries Dense Regular Connective Tissue (in tendon) Dense Regular Connective Tissue- description, function and location -Description: regularly arranged bundles of closely packed collagen fibers with little ground substance; provides great tensile strength when pulled in direction of fibers; fibroblasts are arranged in rosa between fibers -Function: binding and connecting -Location: tendons, aponeuroses and ligaments Dense Irregular Connective Tissue- description, function and location -Description: irregularly arranged bundles of closely packed collagen fibers with little ground substance; provides great tensile strength in all directions -Function: binding and connecting -Location: joint capsules, dermis of skin, submucosa of digestive tract Dense Irregular Connective Tissue (in dermis of skin) Adipose Tissue- description, function and location

 -Description: have adipocytes-- fat cells specialized for fat storage and do not form ground substance or fibers -Function: storage of fat; cushions; insulates -Location: hypodermic of skin, surrounding kidneys, eyes and other organs, within breast tissue Adipose Tissue (in hypodermis of skin) Epidermis composed of epithelial cells (mostly keratinized stratified squamous epithelium) and forms the outermost protective shield of the body Strattum Spinosum cells in this layer shrink during histological preparation, giving them characteristic "spiny" look (spotted cells) Label the 5 layers of the Thick Skin Tactile corpuscules receptors for touch and are most numerous in sensitive areas of the skin (i.e.

lips, fingertips, eyelids) Arrector muscle of hair (arrector pili muscle) contraction of this muscle is what causes the hairs to stand on end in animals and "goose bumps" in humans Burns that include __% or more of the body surface are considered to be life threatening 20% Basal Cell Carcinoma (origin, spreadability, appearance) most common type of skin cancer originates in the s. basale rarely spreads appearance: small, shiny bump on skin surface; as bump enlarges, often develops a central depression and beaded "pearly" edge Basal Cell Carcinoma Squamous Cell Carcinoma (origin, spreadability, appearance) originates in s.

spinosum can spread to lymph nodes if untreated appearance: lesions are raised, reddened and scaly; usually appear on scalp, ears, lower lip, or back of hand Squamous Cell Carcinoma most deadly type of cancer originates often from the melanocytes of a pre-existing mole spreads very quickly and is drug resistant early detection is crucial for survival Malignant Melanoma ABC Rule for early detection of malignant melanoma A = Asymmetry The 3 essential concepts of anatomy and physiology -Moto: form follows function -function always reflects structure -what a structure can do depends on its specific form -Examples: shown in the heart: 2 main pumping chambers have different forms and different functions-- left is more muscular and stronger -Bones can support and protect the body because they contain hard mineral deposits Complementarity of structure and function- example & moto Homeostasis -Dynamic equilibrium of the internal environment -all body systems contribute but the nervous (brain, spinal cord, nerves) and endocrine (pineal, thyroid, pituitary, adrenal glands, pancreas, overt/testis) systems are most important -necessary for health Hierarchy of organization Potential Energy the capability to do work, but not at the moment; found in bonds between different atoms

 within molecules Kinetic Energy occurs when the bonds containing potential energy are broken Isotopes elements having two or more structural variations which have the same number of protons (and electrons) but differ in the number of neutrons they contain Cation -ion with a net positive charge -loss of one or more electrons Anion -an atom that gains one or more electron -becomes a negatively charged ion Ionic bond a chemical bond between atoms formed by the transfer of one or more electrons from one to the other Covalent bond bond created by two atoms sharing one or more pairs of electrons Polar bond 4 major types of macromolecules Carbohydrates -contain carbon, hydrogen and oxygen -mono (1 sugar) & disaccharides (2) -FUNCTION: provide a ready, easily used source of cellular fuel (glucose-- ATP) Starch -plant storage form of glucose Glycogen -animal storage form of complex carbs -located mainly in our muscle, liver and kidneys Proteins -composed of simpler units called amino acids -nonessential: we make, don't have to eat -essential: have to eat, can't make -dipeptide: two amino acids -polypeptide: long chain of amino acids 4 levels of protein structure 1

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Primary structure (linear chain) 2. Secondary structure (spirals & sheets) 3. Tertiary structure (folded) 4.

Quaternary structure (2 or more polypeptide chains) Protein function, and determinants of structure -structure determines function -if you change tmp, pH, sat environment-- can significantly change function -must maintain homeostasis to maintain the environment for the proteins -functions: tissue repair, enzymes, hormones, transport proteins, antibodies, albumin Enzymes proteins that act as catalysts that speed up chemical reactions -lower the activation energy required for a reaction 1) triglyceride (TG) Bases: adenine, guanine, cytosine, thymine Structure: double strand coiled into a double helix RNA (cellular site, functions, sugar, bases, structure) Cellular site: cytoplasm Functions: caries out the genetic instructions for protein synthesis Atomic number -equal to the number of protons in the nucleus and is written as a subscript to the left of the atomic symbol -indirectly tells us the number of electrons (since #protons = #electrons) Mass number -sum of the masses of its protons and neutrons -superscript to the left of the atomic symbol Atomic weight -an average of the relative weights (mass numbers) of ALL the isotopes of an element ATP -the primary

 energy-transferring molecule in cells and it provides a form of energy that is immediately usable by all body cells -STRUCTURE: adenine nucleotide to which 2 additional phosphate groups attach Stem Cells Can give rise to specialized cell types Differentiated (specialized) cells A cell in a multicellular organism that is specialized in its functions, which it may perform in a certain organ or tissue Generated during a developmental process that begins with a fertilized egg extracellular fluids -Include: interstitial fluids, blood plasma, cerebrospinal fluid -transport and dissolving media Interstitial fluid The fluid in tissues that bathes all of our cells and has major and endless roles to play -Cell membrane regulates what is in the ICF and interstitial fluid Negative Feedback (definition and example) -The response of the control system drives the variable in the opposite direction as the original stimulus to the control system -Example: body temp regulation Positive Feedback (definition and example) -Definition: occurs when the response of the system drives the arable in the same direction as the original stimulus; terminating event occurs that ends it -Examples: blood clotting, labor process, circulatory shock, 1.

Metabolism 4 ways that substances can cross the cell membrane Simple Diffusion -non-polar and lipid-soluble substances diffuse directly through the lipid bilayer Facilitated Diffusion 1. bind to protein carriers in the membrane and is ferried across 2. move through water-filled protein channels -Types: carrier-mediated and channel mediated Diffusion the tendency of molecules or ions to move from an area where they are higher in concentration to an area where they are lower in concentration (down/along their concentration gradient) Active Transport -Like carrier-mediated facilitated diffusion--requires carrier proteins that combine specifically and reversibly with the transported substances -Move solutes against a concentration gradient-- cells must expend energy Osmosis The diffusion of a solvent (water) through a selectively permeable membrane -Solvent movement Osmotic Pressure -Force necessary to prevent osmosis through a selectively permeable membrane -The greater the difference in osmolarity (volume) of fluids on each side, the greater the osmotic pressure 1.

Epithelial small and ovoid with relatively long "thorny" processes remove cell debris, wastes, and pathogens by phagocytosis this protective role is important because cells f the immune system have limited access to the CNS Ependymal Cells line ventricles (brain) and central canal (spinal cord) assist in producing, circulating and monitoring of cerebrospinal fluid Oligodendrocytes send out projections which wrap around the axons of neurons-- sheath that is formed in the myelin sheath provide structural framework 1) Satellite Cells: surround neuron cell bodies in ganglia; regulate (similar to astrocytes in CNS) 2) Schwann Cells: surround all axons in PNS; responsible for myelination of peripheral axons; participate in repair process after injury (similar to oligodendrocytes in CNS) 2 Types of supporting cells (and functions) of the PNS Neurons Structural units of the nervous system typically large, highly specialized cells that conduct messages in the form of nerve impulses from one part of the body to another extreme longevity high metabolic rate and require continuous/abundant supply of oxygen and glucose Neurons The cells that initiate and transmit signals The cells that allow us to

 think, reason, possess intellect, and experience emotions Structural and functional unit of the nervous system Myelinated fibers -conduct nerve impulses rapidly -plasma membranes of myelinating cells contain much less protein than those of most body cells-- channel and carrier proteins are absent, making myelin sheaths exceptionally good electrical insulators Unmyelinated fibers Unipolar neurons (description and trigger zone location) -single short process that emerges from the cell body and divides like a T -TZ: where the dendrite branches meet the axon Bipolar neuron (description and trigger zone location) -two processes extend from the cell body, one is a fused dendrite and the other is an axon -TZ: usually on the end of the cell body Multipolar neuron (description and function) -many processes extend from the cell body, all are dendrites except for a single axon -most common neuron type in humans -TZ: axon hillock ("little hill")- initial region of the axon arises from a cone-shaped area Excitable cells Cells that can conduct/propagate electrical changes Voltage the measure of potential energy generated by separated electrical charges (volts/millivolts) Current -the flow of electrical charge from one point to another; can be used to

 do work -inward/ outward: across the cell membrane -capacitive: moving along the cell membrane inward/influx/outward/efflux vs.

capacitative The coming together of opposite charges liberates energy that can be used to do work-- situations in which there are separated electrical charges of opposite sign have potential energy What type of energy do separated opposite charges create? Determined by gradients for ion flow/flux -Electrical How is the magnitude of potential energy of ions determined?

Electrical gradient move along this when ions move toward an area of opposite electrical charge Concentration gradient when ions diffuse passively from an area of their higher concentration to an area of lower concentration Ohm's Law Depolarization decrease in membrane potential the inside of the membrane becomes less negative (moves closer to zero) than the resting potential Includes events in which the membrane potential reverses and moves above zero to become positive increases the probability of producing nerve impulses Hyperpolarization an increase in membrane potential inside of the membrane becomes more negative (moves further from zero) than the resting potential reduces the probability of producing nerve impulses Repolarization The membrane potential returning to rest Graded potentials short-lived, localized changes in membrane potential cause current flows that decrease in magnitude with distance magnitude varies directly with stimulus strength -- the stronger the stimulus, the more the voltage changes and the farther the current flows graded potential stimulus energy must be converted into the energy of _________ postsynaptic potential -when the stimulus is a neurotransmitter released by another neuron, the neurotransmitter is released into a fluid-filled gap called a synapse and influences the neuron beyond the synapse Excitatory postsynaptic potential (EPSP) a local depolarization of the postsynaptic membrane bring the neuron closer to action potential threshold

 neurotransmitter binding opens chemically gated ion channels, allowing Na+ and K+ to pass simultaneously Inhibitory postsynaptic potential (IPSP) a local hyper polarization of the postsynaptic membrane drive the neuron away from action potential threshold neurotransmitter binding opens chemically gated ion channels permeable to K+ or Cl- Temporal summation occurs when one or more presynaptic neurons transmit impulses in rapid-fire order and bursts of neurotransmitter are released in quick succession Spatial summation occurs when the postsynaptic neuron is stimulated simultaneously by a large number of terminals from one or many presynaptic neurons 1.

Resting state (all gated Na+ and K+ channels are closed) 2. Depolarization (Na+ channels are open) 3. Repolarization (Na+ channels are inactivating, K+ channels are open) 4.

Hyperpolarization (some K+ channels remain open, Na+ channels reset) 4 phases of generating an Action Potential Threshold stimuli -can produce depolarizing currents that push the membrane potential toward and beyond the threshold voltage Absolute refractory period When a patch of neuron membrane is generating an AP and its VG sodium channels are open, the neuron cannot respond to another stimuli -The period, from when the Na+ channels open, until they begin to reset their original resting state -It ensure that each AP is separate (all-or-none event) Relative refractory period most Na+ channels have returned to their resting state, some K+ channels are still open, and repolarization is occurring Continuous conduction action potentials triggered only at the gaps electrical signal appears to jump from gap to gap along the axon very fast in comparison (30x) positive feedback system and the Hodgkin cycle -A loop in neurons, where an initial membrane depolarization from the resting value (∼ −70 mV) to the threshold value (∼ −50 mV) -->leads to rapid depolarization of the membrane potential to approach the equilibrium potential for Na+ -The voltage-gated Na+ channels of neurons are responsible -Diameter: the larger the axon's

 diameter, the faster is conducts impulses (less resistance) -Myelination: in myelinated axons, conduction is fast (saltatory conduction) How is the velocity of conduction affected by axon diameter and axon myelination?

Integumentary System - Forms external body covering and protects deep tissues from injury. Synthesizes vitamin D. Houses cutaneous (pain, pressure...) receptors, sweat/oil glands. - Skin, hair, nails - Consists of integument (skin) for protection Skeletal System - Protects & supports body organs. Provides framework for muscles. Bones produce blood cells & store minerals. - joints - Allows for manipulation of the environment, locomotion, & facial expression. Maintains posture & produces heat. - Skeletal muscles, smooth muscles, tendons, ligaments Nervous System - Fast-acting control system of body. Responds to internal/external changes by activating appropriate muscles & glands - Brain, spinal cord, nerves - Glands secrete hormones that regulate growth, reproduction, & metabolism in body cells. - Pineal gland, pituitary gland, thyroid gland, thymus, adrenal gland, pancreas, ovary, testis Endocrine System - Heart pumps blood to blood vessels which transport O2, CO2, nutrients, and wastes. - Capillaries Cardiovascular System Lymphatic (Immune) System - Picks up fluid leaked from blood vessels and returns it to blood.

Disposes of debris in lymphatic stream. Houses WBC (lymphocytes). Immune response mounts attack against foreign substances within body. - Lymphatic vessels, lymph nodes, thoracic duct, spleen, thymus, red bone marrow Respiratory System - keeps blood constantly supplied with O2 and removes CO2. Gas exchange occurs through alveoli walls. - nasal cavity, pharynx, larynx, trachea, lung, bronchus Digestive System - Breaks down food into absorbable units that enter blood & are distributed to body cells. Indigestible foodstuffs are eliminated as feces. - oral cavity, esophagus, stomach, liver, small/large intestines, rectum, anus Digestive System - Eliminates nitrogenous wastes from body. Regulates water, electrolyte and acid-base balance of the blood. - kidney, ureter, urinary bladder, urethra Urinary System - Produce offspring. Testis produce sperm & testosterone. Ducts & glands deliver sperm to female reproductive tract. - Prostate, penis, scrotum, ductus deferens Reproductive System (female) - Produce offspring.

Ovaries produce eggs, estrogen, & progesterone. Other female structures serve as sites for fertilization & development of fetus. Mammary glands produce milk to nourish newborn. - Uterine tube, uterus, vagina - filters blood and produces bile & blood clotting proteins - human liver (4 lobes) vs.

rat liver (5 lobes) gallbladder - stores & secretes bile (breaks down fat) - absent in rats - secretes acid & enzymes to digest churning food - just inferior to left lobe of liver pancreas - long, flat gland located posterior to stomach within omenta - secretes enzymes into small intestine and hormones (insulin) into blood stream omenta - fold of abdominal cavity lining that connects and supports abdominal structures (stomach, liver) spleen - important in blood regulation & WBC development - far left side of abdominal cavity (resembles a leech in rats) small intestine absorbs 90% of nutrients from food mesentery membrane from posterior abdominal cavity that surrounds & anchors small intestine large intestine absorbs water & vitamins, turning digested food into feces cecum first section of large intestine which functions in microbial digestion penis male external excretory (urine) & sex (semen) organ testis glands that produce sperm and male sex hormone (testosterone) scrotum - tube connecting body of uterus to exterior - receptacle of penis; carries sperm to uterine tubes urinary bladder receives urine from kidneys and stores it before excretion kidneys - filter and dispose of waste from blood - surrounded

 by fat pad and connected to urinary bladder by ureters Cardiovascular System (core) descending portion of aorta (largest artery) that supplies blood to core organs inferior vena cava - collects spent blood from periphery veins of lower body and return it to the heart ribs bone structures supporting thoracic cavity and protecting lungs ventricles inferior, larger chambers of heart ventricles interconnected, hollow chambers within the brain contain cerebrospinal fluid and are continuous with the subarachnoid space third ventricle superior, smaller chambers of heart lungs - optimize gas exchange between blood & air - 3 lobes on right, 2 lobes on left thymus gland - functions in maturation of WBC - regresses during adolescence - opening in diaphragm allowing communicating between thoracic & abdominal cavities - inferior vena cava, lymph vessel, and descending abdominal aorta pass through salivary glands produce saliva to aid in digestion trachea wide tube connecting larynx (voice box) to bronchi lungs esophagus muscular tube connecting pharynx (throat) to stomach ganglia (pl.) group of neuron cell bodies in PNS nuclei (pl.) group of neuron cell bodies in CNS nerves group of axons in PNS

 nerves bundles of axons in the PNS; white appearance; have a complex structure consisting of epineurium, fascicles, endoneurium, perineurium tracts group of axons in CNS tracts transmits motor signals from the brain via the cranial nerves and the defending motor ______ of the spinal cord tract a bundle of axons within the CNS that have the sam origin, termination and general function tracts bundles of CNS axons that share a common origin and destination Nervous tissue Highly cellular with 2 major types of cells: support cells and neurons Support cells provide physical and metabolic support to the neurons; most numerous cell type in the nervous tissue Six types: astrocytes, ependymal cells, microglia, oligodendrocytes (CNS); Schwann and satellite (PNS) Dendrites carry electrical signals toward the cell body Axons carry signals away from the cell body Gray Matter highly folded into ridges called gyri (gyrus) divided into lobes by deep grooves called sulci (sulcus) lobes: frontal, parietal, occipital, temporal cerebrum Gray matter: cortex and basal nuclei (ganglia) White matter: commissural,

 association and projection fibers lateral ventricle lie side by side within the cerebrum; separated by a thin membrane called the septum pellucidum contains the choroid plexus- produces cerebrospinal fluid (CSF) continuous with third ventricle via interventricular foramen cerebral aqueduct travels through the midbrain to connect third and fourth ventricles separates corpora quadragemina from cerebral peduncles fourth ventricle chamber located between medulla oblongata and cerebellum continuous with the subarachnoid space with the central canal of the spinal cord Choroid plexus vascular structure contained by each ventricle cerebrospinal fluid (CSF) fills ventricles; produced by the ependymal and cerebellum cells of the choroid plexus cerebral hemisphere primary integrative center of the brain contains basal nuclei (islands of gray matter involved in control of skeletal muscle movements) deep in its white matter longitudinal fissure transverse band of white fibers that connects right and left cerebral hemispheres consists of genu (anterior), body and splenium (posterior) forms roof of lateral ventricle fornix forms floor of lateral ventricle white matter located at core in

 brain made up of axons and dendrites of neurons myelin of axons gives its color diencephalon connects cerebral hemispheres to the brain stem consists of epithalamus, thalamus, and hypothalamus Diencephalon thalamus, hypothalamus, (epithalamus), limbic system epithalamus roof of third ventricle; contains pineal gland pineal gland (body) endocrine gland that secretes melatonin involved with regulation of sleep-wake cycle & some aspects of mood regulates estrus cycle in season breeders (i.e.

sheep) thalamus major relay station of ascending sensory information (performs some initial processing of sensory info by filtering out some signals) contains many different nuclei (groups of related nerve cell bodies within CNS) thalamus THIS STRUCTURE IS NOT PAIRED IN THE SHEEP BRAIN "X" structure; crossing fibers from each eye location of partial decussation of optic nerves pituitary gland (hypophysis) important neuroendocrine "master" gland wedged into sella turcia not part of hypothalamus but connected to it by infundibulum (located immediately anterior to mammilary bodies) ONLY VISIBLE ON MODELS responsible for many of the lower involuntary functions of the brain connects spinal cord to higher brain centers consists of midbrain, pons and medulla oblongata Brain stem fiber tracts and basic control centers components: midbrain, pons, medulla oblongata midbrain (mesencephalon) consists of corpora quadrigemnia and cerebral peduncles corpora quadrigemina two pairs of nuclei (superior and inferior colliculi) which project from the dorsal surface of the midbrain superior colliculus visual reflex center- coordinate head and eye movements when visually tracking a moving object inferior

 colliculus auditory relay center and integrating center for certain auditory reflexes cerebral peduncle paired structure bulging from the ventral surface of the midbrain contain corticospinal motor tracts descending toward spinal cord pons consists of fiber tracts that run in two principle directions surface fibers (transverse fibers & trapezoid body) run transversely to connect with the cerebellum, while the deeper fiber tracts run longitudinally to form ascending and descending tracts contain nuclei involved in involuntary control of breathing Pons white matter of cerebellum takes on look of a tree "tree of life" cerebellar peduncles tracts which connect and allow cerebellum to communicate with cerebrum, brain stem and spinal cord anterior connects with cerebrum, diencephalon & brain stem, middle connects to pons and posterior connects to medulla oblongata & spinal cord hemorrhage the loss of blood from a vessel when the vessel is located in the coverings of the brain it is called a brain ________.

this condition can be life-threatening since the skull is unyielding, any pooling of blood under the skull will exert pressure on the brain cranial nerves nerves of the PNS that communicate with the brain spinal nerves nerves of the PNS that communicate with the spinal cord Number: I Function: sense of smell (olfaction) Location: cribiform plate of ethmoid bone into nasal cavity olfactory cranial nerve: number, type, function and location Number: II Location: distal to optic chiasma connecting to eyes Optic cranial nerve: number, type, function and location In order in which they attach to the brain, from anterior to posterior In which order are the cranial nerves arranged?

Number: III Function: motor impulses to 4 of 6 extrinsic eye muscles Location: ventral surface of cerebral peduncles Oculomotor cranial nerve: number, type, function and location Number: IV (4) Function: motor impulses to superior oblique muscle of eye Location: immediately posterior to inferior colliculus Trochlear cranial nerve: number, type, function and location Number: V (5) Function: sensory info from head & face; motor signals to chewing muscles Location: lateral surface of pons Trigeminal cranial nerve: number, type, function and location Number: VI (6) Function: motor impulses to lateral rectus muscle to abduct eye Location: medial section of trapezoid body Abducens cranial nerve: number, type, function and location spinal cord dual function: gray matter: functions as an integrating center by receiving sensory info and transmitting motor impulses to effector organs white matter: transmits impulses to and from the brain and other levels by way of its ascending and descending tracts surrounded within the vertebral canal by meninges and cerebrospinal fluid spinal nerves (in the PNS) responsible for conducting sensory impulses from the receptors to the spinal cord and for transmitting the motor impulses

 from the spinal cord to the effector organs Medullary cone terminal end of spinal cord Cervical enlargement region of spinal cord where nerves to upper appendages branch off lumbosacral enlargement region of spinal cord where nerves to lower appendages branch off cauda equina extension of meninges from medullary cone to coccygeal region dorsal (posterior) horns comprise posterior portion of "H" in spinal cord contain nerve cell bodies of interneurons dorsal root ganglion small bulge in the dorsal root containing cell bodies of sensory neurons ventral (anterior) horns comprise anterior portion of "H" contain nerve cells bodies of motor neurons that control skeletal muscles enlarged in cervical and lumbar regions of spinal cord because they contain nerve cell bodies of motor neurons innervating skeletal muscles of upper and lower extremities lateral horns located only in the regions of the spinal cord where neurons of sympathetic division of the autonomic nervous system are present (thoracic and upper lumbar regions) contain nerve cell bodies of sympathetic preganglionic neurons gray commissure connects gray matter on each half of spinal cord transmits info form one side of spinal cord to the other (decussation) central canal located at center of gray commissure contains ependym

al cells which produces CSF runs length of spinal cord and continuous with ventricles of brain Fascicle groups of endoneurium- encased axons are arranged into bundles perineurium collagenous sheath surrounding each fascicle epineurium what binds together multiple fascicles by an even coarser coat of dense fibrous connective tissue that surrounds the entire nerve Intervertebral foramina spinal nerves enter and exit the bony vertebral column through openings formed between adjacent vertebrae called ________ reflex an involuntary response to a stimulus reflex involuntary direct response to a stimulus reflex arc the pathway through which a stimulus can directly cause a response without any conscious or voluntary control or input 1.

Receptor 5 components of the Reflex arc Receptor Component of the Reflex arc that is usually part of an afferent neuron, but can be a specialized cell that synapses onto the afferent neuron converts stimulus energy into electrical signals called action potentials receptor afferent neuron or specialized cell that converts stimulus energy into action potentials (electrical signals) afferent pathway component of the Reflex arc that consists of sensory neuron that conducts action potential from receptor to CNS Afferent pathway sensory pathway in which information is passed from the stimulus to the CNS afferent pathway sensory neuron conducting AP from receptor to CNS integrating center region of the CNS where afferent neuron synapses with one or more neurons location of initial processing of sensory info which occurs even though we have no conscious perception of this activity the more complex the reflex, the greater will be the number of CNS synapses involved in the reflex arc integrating center -region of CNS where initial processing of sensory info occurs -may include multiple synapses for complex pathways efferent pathway consists of a motor neuron that carries a signal (command) from integrating center to effector cell Efferent pathways motor pathways in which information descends from the CNS back to the dorsal horn on the spinal cord (effectors) efferent pathway

 motor neuron that carries a signal command from integration center to effector effector cells/tissues/organs that respond to action potentials being carried in efferent pathway reflex arcs cause these cells to either increase or decrease their activity Ex: muscle, epithelial or connective tissue cells effector -cells/tissues/organs that respond to AP in efferent pathway -signal may cause increase or decrease in activity somatic reflexes serve to activate skeletal muscle following application of a stimulus somatic reflex function is to resist lengthening of skeletal muscle present in all skeletal muscle this reflex causes the muscle to contract and therefore resist stretching and returning the muscle to its original length when a muscle is rapidly stretched myotatic (stretch) reflex -resists stretching of skeletal muscle, helping to balance & maintain posture -present in skeletal muscles the type of proprioreceptor involved with the myotatic reflex contains several thin muscle calls called intrafusal muscle fibers enclosed in a connective capsule muscle spindle receptor in myotatic reflex latent period the time it takes for electrical transmission of action potentials along the neurons involved in the reflex and chemical transmission across synapse(s) involved in the reflex a brief period of time after the stimulus is applied during which no response is observed latent period -time from stimulus to initiation

 of movement (response) maximum excursion the amplitude (or size) of the reflex response (in degrees) maximum excursion amplitude of the response (measured in degrees for the knee-jerk) In the orbits of the skull Where are the eyes located?

extrinsic eye muscle contraction in the proper sequence makes it possible for our eyes to track a moving object fibrous tunic: outermost layer of dense connective tissue; consists of sclera and cornea vascular tunic: middle layer; consists of choroid, ciliary body and iris nervous (sensory) tunic: innermost layer consisting of retina and pigmented epithelial layer Name/define the 3 major tunics (layers) of the eye superior rectus: elevate & adduct eye inferior rectus: depress & adduct eye lateral rectus: abduct eye Name/action of the 6 extrinsic eye muscles Superior/inferior/medial rectus & inferior oblique: CN III Superior oblique: CN IV The cranial nerves that innervate each extrinsic eye muscle cornea transparent portion of fibrous tunic; curved to bend light as it enters sclera "White of eye"; continuous with cornea; tough collagenous layer that helps maintain shape of eye; serves as attachment site for extrinsic eye muscles optic nerve (CN II) pierces sclera at posterior aspect of eye; conducts signals from retina to brain choroid posterior portion of vascular tunic; contains many blood vessels and dark pigments that absorb light c

iliary body located at anterior edge of choroid and attaches to lens ciliary muscle smooth muscle of ciliary body; controls shape of lens ciliary process extensions from ciliary muscle; attach to suspensory ligaments suspensory ligaments attach ciliary processes to lens lens performs final fine focusing of light rays transparent to allow light to pass through changes in thickness and degree of curvature when ciliary muscles relax/contract to alter its refractive power (accommodation) iris most anterior portion of vascular tunic; colored part of eye pupil posterior segment (vitreous or postremal chamber) space posterior to lens; filled with vitreous humor (body) anterior segment space anterior to lens; filled with aqueous humor anterior chamber space between cornea and iris posterior chamber space between iris and lens neural layer layer of the retina that is composed of 3 layers of nervous cells: photoreceptors, bipolar cells and ganglion cells photoreceptors(rods and cones) outermost layer of retina made up of 5 to 7 rows of nuclei; photosensitive cells which receive stimulus from light bipolar cells middle layer of neural layer which contains numerous rows of nuclei; conduct electrical signals generated by rods and cones to ganglion cells Ganglion cell layer 3 major regions of the

 ear inner ear Which region of the ear functions in equilibrium?

inner ear consists of a hollowed out region of fluid-filled bony canals within the temporal bone called the osseous labyrinth and a system of fluid-filled membranes and ducts contained within called the membraneous labyrinth perilymph: fluid filling osseous labyrinth endolymph: fluid filling membraneous labyrinth within the petrous part of the temporal lobe Location in the skull of the 3 major regions of the ear auricle and external acoustic meatus 2 parts of the external ear auricle (pinna) outer shell of skin and cartilage attached to side of head; serves to collect and direct sound waves into external acoustic meatus external acoustic meatus canal extending about one inch into temporal bone; terminates at tyrannic membrane (eardrum) middle ear consists of a small air-filled cavity in the temporal bone between the tyrannic membrane and inner ear; consists of 3 ossicles (small bones) malleus outermost ossicle attached to tympanic membrane; referred to as "hammer" due to its shape incus (incudis) middle ossicle; referred to as the "anvil" due to its shape stapes innermost ossicle; referred to as the "stirrup"; fits into oval window of inner ear

 nasopharynx uppermost part of the pharynx in which the middle ear is connected to through a duct called the Eustachian tube vestibule- center portion that contains oval window semicircular canals (anterior/posterior/lateral)- branch off vestibule; function in minting equilibrium cochlea- branches off vestibule opposite semicircular canals; shaped like snail; function in hearing Name/define the 3 semicircular canals of the osseous labyrinth scala vestibuli begins at oval window and continuous with vestibule; filled with perilymph scala tympani terminates at membrane-covered round window, filled with perilymph scala media (cochlear duca) triangular tube located between scala vestibuli and scala tympani; filled with endolymph vestibular membrane thin membrane separating scala media from scala vestibuli basilar membrane thicker membrane separating scala media from scala tympani spiral organ (organ of Corti) located in scala media; lies on basilar membrane; contains receptor (hair) cells of hearing hair cells sensory cells in spiral organ that have cilia on their exposed borders; nerve fibers leading from these cilia become part of vestibulocochlear nerve tectorial membrane gelatinous-like membrane;

 forms canopy over hair cells general senses provide us with info about pain, temperature, touch, pressure, vibration and position general sense provides info about pain, temp, pressure, vibration, position special sense provide info about vision, smell (olfaction), hearing, taste (gustation) and balance (equilibrium) special senses provide info about vision, olfaction, gustation, audition, equilibrium transduction the process of converting stimulus energy into an electrical signal mechanoreceptors receptors for touch, pressure, vibration and position; stimulated with their membrane is distorted mechanoreceptors stimulated when membrane is distorted receptive field the area throughout which each sensory receptor cell is sensitive to changes in the environment the size varies among individual receptors and between receptors of different senses the smaller it is, the better able you are to localize stimuli receptive field -area covered by sensory receptor -smaller receptive field = easier to locate stimulus myopia near-sightedness; light rays are directly in from of the retina myopia can see near, cannot see far; near-sighted causes: eyeballs too long, lens too bulged; the convergence of the light happens in front of the retina Corrections: by using a concave lens that diverges the light, so that it converges in the correct spot myopia -

light rays directed in front of retina -requires concave lenses sharpness of vision color blindness congenital defect resulting from a deficit of one or more types of cones; sex-linked trait and more prevalent in males than females color blindness condition due to a congenital lack of one or more cone pigments color blindness congenital visual defect resulting from cone type deficit (blue, green, and/or red) astigmatism irregularities in the cornea and/or lens, which cause some portions of an object to appear clear, while other parts appear blurry astigmatism parts of visual field appear blurry due to irregularities in cornea/lens emmetropia condition of normal vision, when light rays are directed into the retina emmetropia the term for normal vision hyperopia far-sightedness; condition in which light rays are directed behind the retina; difficulty seeing objects that are close-up hyperopia causes: eyeballs too short, lens too flat Corrections: pre-converge the light before it comes in by the use of a convex lens presbyopia the ability to accommodate that is virtually gone after the age of 60 presbyopia loss of ability of lens to accomodate (loss of lens elasticity) Conduction deafness transmission of sound waves through the middle ear to

 the oval window is impaired (i.e.

ear infection) conduction deafness occurs when something hampers spun conduction in the fluids on the internal ear conduction deafness transmission of sound waves through middle ear to oval window is impaired sensorineural deafness transmission of signals from the hair cells in the cochlea to the auditory cortex is impaired by damage to one to more components of the auditory pathway (i.e.

playing music too loud) sensorineural deafness results from damage to neural structures at any point from the cochlear hairs to auditory cortical cells; usually results from loss of hair cells throughout life sensorineural deafness transmission of signals is impaired by damage to auditory pathway Central nervous system: brain and spinal cord; integrative and control centers Peripheral nervous system: cranial nerves and spinal nerves; communication lines between CNS and the rest of the body Divisions of the Nervous system, function, and components Sensory (afferent) division: somatic and visceral sensory ner ve fibers; conducts impulses from receptors to the CNS Motor (efferent) division: motor nerve fibers; conducts impulses from the CNS to effectors (muscles and glands) Subdivisions of the PNS, components and functions Somatic nervous system: somatic motor (voluntary); conducts impulses from the CNS to skeletal muscles Autonomic nervous system: visceral motor (involuntary); conducts impulses from the CNS to cardiac muscle, smooth muscle and glands Subdivisions of the motor (efferent) division and functions Sympathetic division: mobilizes body systems during activity Parasympathetic division: conserves energy; promotes housekeeping functions during rest Subdivisions of the Aut

onomic nervous system and function sensory (afferent) neurons transmit impulses from sensory receptors in the skin or external organs TOWARD or INTO the CNS; bipolar and unipolar neurons motor (efferent) neuron carry impulses AWAY FROM the CNS to the effector organs (muscles and glands) of the body; mostly multipolar gyri Gray: ganglia (collections of neuron cell bodies) White: Nerves (bundles of axons) PNS components of gray and white matter Gray: neural cortex (surface), centers (collections of neuron cell bodies), nuclei (collections of neuron cell bodies in interior), higher centers (most complex in brain) White: Tracts (bundles of axons that share common origin and destination), columns (several tracts that form anatomically distinct mass) -collections of myelinated axons makes color CNS components of gray and white matter Cortex gray matter on the surface of the brain; outer edge nuclei collections of neuron cell bodies in the interior of the CNS dura mater (outermost layer) arachnoid mater (deep to the dura mater pia mater (on top of brain) Meninges (coverings of CNS) of the brain Each choroid plexus consists of a knot of porous cap

illaries surrounded by a single layer of ependymal cells joined by tight junctions and have long cilia.

Fluid leaking form capillaries is processed by the ependymal cells to form the CSF in the ventricles (ion pumps & active transport) How is CSF produced? the protective mechanism that helps maintain the brain's stable environment impermeable tight junctions between capillary endothelial cells selective, not absolute; nutrients such as glucose move passively by facilitated diffusion ineffective against fats, fatty acids, oxygen, carbon dioxide and and other fat-soluble molecules Cerebrospinal fluid found in and around the brain and spinal cord watery "broth" similar composition to blood plasma helps nourish the brain and some evidence that it carries chemical signals contains less protein than plasma and its ion concentrations are different (contains more Na+, Cl- and H+, and less Ca2+ and K+ than plasma) cerebrospinal fluid nutrient rich broth bathing the brain and spinal cord basal nuclei (ganglia) help control skeletal muscle movements midbrain connect different parts of the same hemisphere short fibers connect adjacent gyri long fibers are bundled into tracts and connect different cortical lobes commissural fibers connect corresponding gray areas of the two cerebral hemispheres (i.e.

corpus callosum) projection fibers Either enter the cerebral cortex from lower brain or cord center or descend from the cortex to lower areas Tie the rest of the nervous system to body's receptors and effectors form the internal capsule at the top of the brain stem decussation crossing or intersection of two or more things to form an X contralateral referring to the opposite side ipsilateral the end of the tract is on the same side compared to the start of the tract primary somatosensorycortex resides in the post central gyrus of the parietal lobe neurons in this gyrus receive info from the general (somatic) sensory receptors in the skin and from proprioreceptors in skeletal muscles, tendons and joints the neurons then identify the body region being stimulated, an ability called spatial discrimination somatosensoryhomunculus the amount of sensory cortex devoted to a particular region is related to that region's sensitivity (how many receptors it has), not its size in humans, the face and fingertips are the most sensitive so these regions make up the largest part of the ________________.

somatosensoryassociation cortex -integrates sensory input from primary somatosensory cortex for understanding of objects - determine size, texture, and relationship of object and compare to previous experiences rods detect light across the visual spectrum; located all over the retina of the eye cones higher densities in macula lute and fovea centralis photopigment is one of three different opsins + retinal refraction light bends when light hits new medium (cornea, fluids, and lens) at oblique angle concave when the lens diverge light convex when the lens converge light prebyopia a hyperopia associated with aging; the inability of the lens to accommodate; as we age our lens bulges more Accommodation: contract ciliary muscles, suspensory ligaments loosen, lens bulges Pupillary reflex: radial relaxes/circular contracts, pupil constricts Convergence: eyes converge to focus image on fovea What must the eye do when focussing on near objects?

(accommodation, pupillary reflex, convergence) Accommodations: ciliary muscles relaxed, suspensory ligaments tighten, lens flat Pupillary reflex: radial contracts/circular relaxes, pupil dilates Convergence: eyes straight ahead or same side What must the eye do when focussing on far objects? (accommodations, pupillary reflex, convergence) light comes in, passes through the cornea through the aqueous humor, pass through the axons of the bipolar and ganglion cells reaches the photoreceptors in the retina Describe the order of the passage of light through the eye. rhodopsin rapidly bleaches & rods inhibited & cones stimulated What happens with light adaptation (dark to light)? cones not stimulated and so rhodopsin accumulates so rods eventually become more sensitive What happens with dark adaptation (light to dark)? 3 Major cerebral nuclei and their associations cell bodies of first-order sensory neurons What types/parts of neurons are found in dorsal root ganglion? sensations The conduction of a quality or state (adequate or usual stimulus energy…light, sound, etc.) of our nerves to consciousness, excited by an external cause (any stimulus of the pathway).

labeled line theory individual receptors preferentially transduce information about an adequate stimulus individual primary afferent fibres carry information from a single type of receptor Law of specific nerve energies the nature of perception is defined by the pathway over which the sensory information is carried. the origin of the sensation is not important.

Therefore the difference in perception of seeing, hearing, and touch are not caused by differences in the stimuli themselves but by the different nervous structures that these stimuli excite exteroceptors: sensitive to stimuli outside the body interoceptors: respond to stimuli within the body proprioceptors: respond to internal stimuli; sense position and/or movement 3 classifications of sensory receptors by source of stimulus Free nerve ending (non encapsulated): respond chiefly to temp and painful stimuli, some to tissue movements caused by pressure (tactile discs, hair follicle receptors) Encapsulated: consist of one or more fiber terminals of sensory neurons enclosed in a connective tissue capsule (tactile, lamellated, bulbous corpuscles, muscle spindles, tendon organs, joint kinesthetic receptors) Sense organs: taste buds, ears, eyes 3 classifications of sensory receptors by complexity of structure mechanoreceptors: respond to touch, pressure, vibration, stretch thermoreceptors: respond to temp changes photoreceptors: respond to light chemoreceptors: respond to chemicals in solution osmoreceptors: interoceptors that sense osmalarity of body fluids baroreceptors: specific type of muchanoreceptors that sense changes in pressure nociceptors: respond to potentially damaging stimuli that

 result in pain 7 classifications of sensory receptors by stimulus energy touch somatosensorymodalities Tonic: provide a sustained response with little or no adaptation (nocirecptors & most proprioceptors) Phasic: rapidly adapting; often give bursts of impulses at the beginning and end of stimulus (lamellar and tactile corpuscles) Tonic vs.

phasic sensory receptors (classification by type of adaptation) peripheral adaptation some sensory neurons can adapt to constant stimuli; that is, they begin to require stronger stimulus input to depolarize, this is know as what? central adaptation peripheral neurons send signals, but those signals don't make it to awareness (i.e. getting used to a strong smell); ignoring senses from the periphery generator potential when a receptor region is part of a sensory neuron, the graded potential is called ___________, because it generates action potentials receptor potential when a receptor is a separate cell, the graded potential is called ___________, because it occurs in a separate receptor cell; changes the amount of neurotransmitter released by the receptor cell onto the sensory neuron.

greater stimulus ----> greater receptor potential (generator potential) ----> more frequent action potentials Greater stimulus ---> greater _________----> more frequent action potentials perception posterior column pathway (fasciculus cuneatus & fasciculus gracilis)- fine touch, pressure, proprioception spinothalamis (anterior and lateral) - pain, temp, deep pressure spinocerebellar (anterior and posterior) - transmits proprioceptive info only to cerebellum Ascending tracts used in the somatosensory processing posterior column (fasciculus cuneatus & fasciculus gracilis) modalities of fine touch, pressure and proprioception carried through which ascending tract? spinothalamictract (anterior and lateral) modalities of pain, temperature and deep pressure are carried through which ascending tract?

dermatome an area of skin innervated by the cutaneous branches of a single spinal nerve referred pain pain stimuli arising in one part of the body are perceived as coming from another part olfaction (smell) Order of the gustatory pathways reflection (light bouncing off of a surface) The _______ of light by objects in our environment accounts for most of the light reaching our eyes white reflect Things that look white _____ all wavelengths of light, whereas black objects ______ them all.

retinal absorbs light & changes shape - visual pigment activates visual pigment activates transducen (G protein) transducen activates phosphodiesterase (PDE) PDE converts cGMP into GMP, causing cGMP levels to fall cGMP-gated cation channels close, resulting in hyperpolerization (light-receptor-G protein-enzyme-2nd messenger) Order of events in phototransduction photoreceptors influence bipolar cells bipolar cells influence ganglion cells (on and off center) ganglion cell axons extend through optic nerve and tracts and synapse on neurons in LGN of thalamus (also collaterals to SCN & superior colliculus) thalamic neurons project to primary visual cortex in occipital lobe Order of visual pathway cause: prolonged vitamin A deficiency stereoscopic vision two eyes located side-by-side in the front of their heads.

Thanks to the close side-by-side positioning, each eye takes a view of the same area from a slightly different angle panoramic vision bigger field of vision, but since the eyes are located toward the side of the head, do not have a sense of depth perception amplitude height of the sine wave crests reveals a sound's intensity, which is related to its energy, or the pressure differences between its compressed and rarefied intracellular Endolymph similar to ___________ fluid Scala tympani/vestibuli has perilymph, similar to _________ fluid –1st order neuron (cell bodies in spiral ganglia) at base of hair cells synapse in medulla cochlear nucleus –2nd order to superior olivary nucleus (pons-medulla junction) –3rd order neurons to inferior colliculus (coordinates motor response to sounds) –4th order neurons to MGN of thalamus –5th order neurons to auditory cortex in temporal lobe/auditory association areas Order of auditory pathway Sound waves vibrate the tympanic membrane Auditory ossicles vibrate.

Pressure is amplified Pressure waves created by stapes pushing on the oval window move through fluid in scala vestibuli Sounds w/ frequencies below hearing travel through helicotrema & don't excite hair cells Sounds in the hearing range go through the cochlear duct, vibrating the basilar membrane & deflecting hairs on inner hair cells.

Pathway of sound waves serial processing the whole system works in a predictable all-or-nothing manner one neuron stimulates the next, which stimulates the next, and so one, eventually causing a specific, anticipated response Examples: spinal reflexes and sensory pathways from receptors to the brain parallel processing inputs are segregated into many pathways and different parts of the neural circuitry deal simultaneously with the info delivered by each pathway Example: stepping on a tack-- pain and pressure impulses are speeding up your brain along pathways that allow you to decide to rub it or seek first aid lateralization the division of labor between the cerebral hemispheres, each having abilities not completely shared by its partner lateralization ability to hear sound based on its location in relation to the ear (left, right) Cerebral Dominance Designates the hemisphere dominant for language (left hemisphere in 90% of people)/correlation between this and handedness blood pressure closest distance at which one can see an object in sharp focus photopupillary reflex circular smooth muscles of iris contract in response to light pupillary distance reflex pupil changes size based on distance of focus (far = dilate, near = constrict) sensory receptors provide sensory info to CNS Rhine Test -compares air conduction of sound vs.

bone conduction -Normal: hear sound longer through air conduction Snellen method measures visual acuity (sharpness of vision) based on ability to read letters of varying sizes in a chart Weber Test -tests for deafness via lateralization -tuning fork placed on top of head two point discrimination threshold -tests ability to differentiate between two points on skin being stimulated simultaneously -depends on size of receptive field threshold the intensity that must be exceeded for a certain reaction intrafusal fibers -thin muscle cells in muscle spindle -enclosed in connective tissue capsule extrafusal fibers -surface membrane of hyaline cartilage -avascular, allows for diffusion of O2 & nutrients -contains fibroblasts (produces matrix & collagen) Fibrous Cartilage -thick collagen fibers in matrix with chondrocytes between Fnx: support, resist compression, absorb shock Location: intervertebral discs, pubic symphysis, menisci of knees compact bone -lamellae (layers) make up osteon spongy (cancellouos or trabecular) bone characterized by trabeculae - slender pink slivers composed of lamellae that enclose morrow cavities (filled with red bone marrow).

myocyte -has unique ability to contract striated muscles composed of myofibrils (contractile elements) with even smaller contractile units (sarcomeres) non-striated muscles composed of myofibrils --> myofilaments (actin & myosin), but not arraged into sarcomeres sarcomere formed by myofilaments (myosin & actin) arranged in overlapping dark-light segments (striations) Skeletal Muscle -most abundant tissue (40% body mass) -striated, voluntary, multinucleated -found only in the heart -subtly striated, involuntary, one nucleus Smooth Muscle -smooth, sustained contractions of internal organs -involuntary, non-striated, single nucleus sac filled with synovial fluid located between tendons and bones bursitis inflamation of bursa due to injury or repetitive motion joint dislocations (luxations) -normal arrangement of bones is disturbed/displaced -tear joint capsule and surrounding ligaments/tendons joint dislocation (luxations) when the normal arrangement of the bones involved in a particular joint is disturbed or displaced subluxation -articular surfaces not aligned subluxation a partial dislocation- the articular surfaces are no longer

 aligned correctly, but are still in partial contact sprain stretch/tear ligaments sprain the stretching or tearing of ligaments when the joint has been overstressed or injured, but no dislocation or fracture strain

Question: The band/sheet of connective tissue under the skin in human anatomy, chiefly of collagen, which stabilizes/supports organs and muscles, is?
Answer: Fascia