ZOOL 2403 Boros lecture exam 3 with 100% correct answers 2024

5 special senses - answer-olfaction, taste, vision, hearing, equilibrium and balance where is the olfactory pathway located? - answer-on the temporal lobe of the cerebral cortex what is the pathway of odor the olfactory cortex? - answer-odor goes to the olfactory receptors, pass through cribriform plate of ethmoid bone, CN I synapses on neurons in olfactory bulbs, whose axons form olfactory tract, and then goes to the olfactory cortex gustatory (definition) - answer-taste Where are taste receptors located? - answer-deep in the grooves of taste buds what are the 6 primary taste sensations? - answer-sweet, salty, sour, bitter, umami, and water describe the gustatory pathway - answer-taste goes to taste receptors-CHs-medulla-gustatory cortex What are the two nerves associated with the gustatory pathway? - answer-Facial nerve (CN VII): anterior 2/3 of tongue Glossopharyngeal (CN IX): posterior 1/3 of tongue how many layers of the eyeball are there - answer-3 what kind of connective tissue makes up the outer layer of the eyeball? - answer-dense connective tissue what kind of connective tissue makes up the middle layer of the eyeball? - answer-loose connective tissue layer what kind of tissue makes up the inner layer of the eye? - answer-nervous tissue layer called retina what is the sclera and where is it located in the eye? - answer-white sheath that protects the eyeball; fibrous tunic that surrounds the eye what is the cornea and where is it - answer-its the transparent anterior continuation of the sclera that protects the lens its AVASCULAR (therefore it can be transplanted) what is the choroid? - answer-layer surrounding the eye that contains blood vessels that supply oxygen and nutrients to the tissues of the eye what is the ciliary body , where and what does it do - answer-anterior continuation of the choroid, contains smooth muscle (ciliary muscles) that controls the shape of the lens for focusing an object what is the iris and what is its primary function? - answer-the iris is smooth muscle surrounding the pupil, giving eye color and changes pupil size to regulate amount of light entering/exiting eye what is the retina? - answer-inner layer of nervous tissue within the eye that contains photoreceptors (rods and cones) What are rods and where are they found? - answer--receptors activated by dim light -used for night vision -black and white vision -used for peripheral vision --found in the retina What are cones and where are they found? - answer--receptors activated by bright light -used for daylight vision -color vision -used for central vision --found in the retina what layer of the eye is the choroid located? - answer-the middle layer what layer of the eye is the sclera located in ? - answer-outer layer what layer of the eye is the ciliary body located? - answer-middle layer are the cornea and the choroid in the same layer of the eye? - answer-no, cornea is in the outer layer and the choroid is in the middle during sympathetic stimulation, what happens to the iris/pupil? - answer-fight or flight/ pupils will dilate during parasympathetic stimulation, what happens to the iris/pupil? - answer-rest and digest stage; constrictors contract and pupil gets smaller what is the transparent gel located in the posterior cavity? - answer-vitreous humor what is the vitreous humor made out of, and when is it produced? - answer-transparent gel thats 99% H2O, not produced until 4-5 years old what are floaters (in terms of the eye)? - answer-detached cells you can see in your vision whats so important about vitreous humor? - answer-creates proper pressure within the eye and helps keep retina in place, maintains vision list the visual pathway to consciousness - answer-light-optic receptors-optic nerve-optic chiasm-optic tract-thalamus-visual cortex eye muscles are ______ muscles - answer-skeletal action of inferior rectus - answer-eye looks down, oculomotor nerve (III) action of medial rectus - answer-eye looks medially, oculomotor nerve (III) action of superior rectus - answer-eye looks up, oculomotor nerve (III) action of lateral rectus - answer-eye looks laterally, abducens nerve (VI) action of inferior oblique - answer-eye rolls, looks up and laterally out, oculomotor nerve (III) action of superior oblique - answer-eye rolls, looks down and laterally out, trochlear nerve (III) what is the most external part of the ear and what does it do - answer-the auricle acts like a horn or funnel, amplifying sound and channeling it into external acoustic canal what are the little bones in the middle ear called? - answer-ossicles: malleus, incus, and stapes Semicircular canals are in what part of the ear? - answer-Inner sound waves travel along the ____ ___ ____ and arrive at the ______ _______ - answer-external ear canal; tympanic membrane vibrations of the ____ membrane causes little bones to move called ____ - answer-tympanic; ossicles movement of the ___ at the ___ ___ generates pressure waves in the fluid filled _____ of the inner ear - answer-stapes, oval window, cochlea pressure waves of the inner ear eventually travel to the ___ ____ - answer-round window the cochlea contains 3 ___ ____ - answer-circular chambers the floor of the middle chamber is called the _____ ______ and when it moves ____ ___ are stimulated and move - answer-basilar membrane; hair cells where are the tops of hair cells embedded? - answer-the tectorial membrane when hair cells in the ear bend, this opens ____ ___ , activates ___ ____ and stimulates _____ - answer-opens ion channels, activates hair cells, and stimulates CN VIII how does auditory information travel from CN VIII? - answer-info travels via the thalamus to the auditory cortex in the temporal lobe where it reaches consciousness what is the vestibular apparatus? - answer-in inner ear, connected to CN VIII, composed of semicircular canals(saccule and utricle). associated with equilibrium and balance Semicircular canals contain a structure called a ____ filled with a ___ _____ - answer-cupula, gelatinous substance what stimulates the semicircular canal within the vestibular apparatus? - answer-head rotation saccule and utricle - answer-contain hair cells (receptors) and are stimulated by gravity (starting/stopping in elevator), and linear acceleration (starting/stopping in a car) what are the hair cells in the vestibular apparatus embedded in? - answer-a gelatinous material containing calcium carbonate crystals called otolith Somatic Sensory Pathway - answer--Conscious sensory info: 1. originates at receptors in periphery 2. ascends on axons of sensory neurons in white matters of spinal cord 3. is relayed to cell bodies of sensory neuron in the gray matter of cerebral cortex, where it becomes conscious Somatic Motor Pathway - answer--Conscious motor commands 1. originate in cell bodies of motor neurons in gray matter of the cerebral cortex 2. descend on axons of motor neurons through the white matter of the spinal cord 3. are relayed to cell bodies of spinal cord motor neurons whose axons carry info to skeletal muscles what does the ANS coordinate? - answer-functions of the cardiovascular system, respiratory system, digestive system, urinary system, and reproductive systems what are some similarities between the somatomotor system and the ANS? - answer-both are motor systems to innervate muscles what type of muscle does the somatic nervous system innervate? - answer-skeletal muscle; voluntary system; INITIATES skeletal muscle contraction what type of muscle does the autonomic nervous system innervate? - answer-smooth, cardiac muscle; involuntary; COORDINATES smooth or cardiac muscle contraction (not initiate) 1 neuron system - answer-somatomotor- their axons synapse directly on skeletal muscles in periphery 2 neuron system - answer-ANS- neuron #1 is preganglionic neuron whose cell body is in CNS and synapses with neuron #2, a postganglionic neuron whose cell bodies located in ganglia in PNS synapse on smooth/cardia muscles in periphery sympathetic division innervates - answer-mainly vascular, smooth muscle -blood vessels are everywhere so sympathetics are everywhere (whole body) parasympathetic division innervates - answer-only visceral smooth muscle (like gut) -parasympathetics are more localized responses, restricted to a single organ where are visceral organs? examples - answer-only in trunk and head. thorax, abdomen, pelvis, and glands in the head pre ganglionic neuron cell bodies are located in the - answer-spinal cord-lateral gray horns T1-L2 post ganglionic neuron cell bodies are located in - answer-ganglia epinephrine is secreted from - answer-the adrenal medulla sympathetic chain ganglia target - answer-visceral effectors in the thoracic cavity, head, body wall, and limbs collateral ganglia target ___ organs - answer-visceral effectors in abdominopelvic cavity adrenal medullae target - answer-organ systems throughout the body through the release of hormones into the circulation when a crisis hits the body and the sympathetic division is activated, what functions increases/decrease? - answer-increase:respiratory rate, heart rate, blood pressure, metabolism, alertness, and sweating decrease: digestive and urinary functions after fight or flight is over and the body begins to return to normal functions, what increase/decrease? - answer-decrease: heart rate, blood pressure, metabolic rate increase: glandular secretions, digestive tract mobility, and the urge to urinate and defecate pre ganglionic neuron cell bodies are located in the - answer-brain stem and spinal cord post ganglionic neuron cell bodies are located in - answer-ganglia, either the head or the walls of the viscera(internal organ) Parasympathetic nerves: - answer-1. from the brain stem travel with cranial nerves to reach their targets in the: head, thorax, abdomen 2. from the spinal cord travel with spinal nerves to reach their targets in the: pelvis functions of epithelial tissue - answer-lines all body surfaces, serves as a barrier, provides protection for deeper tissue layers, regulates exchange of substances for deep tissue layers(through membrane) and performs absorption and secretion what is unique to epithelial tissue in comparison to other tissues? - answer-epithelial tissue is composed of ONLY epithelial cells characteristics of epithelial tissue? - answer-forms continuous sheet, avascular, receives nutrients via diffusion, connected to CT by basement membrane(basal lamina) epithelial cell characteristics - answer-polar, each cell has a apical surface, lateral surface, and basal surface, undergo frequent mitosis apical surface of epithelial cell - answer--furthest from the basement membrane -may contain microvilli or cilia lateral surface of epithelial cell - answer--contains specializations such as "junctions" basal surface of epithelial cell - answer--closest to the basement membrane epithelial cell types - answer-squamous, cuboidal, and columnar simple epithelial tissue types - answer-squamous, cuboidal, columnar, pseudostratified (one layer of cells, all cells are in contact with the basement membrane) stratified epithelial tissue types - answer-keratinized, unkeratinized, transitional (urothelium) (composed of more than 1 layer of cells, for protection) squamous cell activity level - answer-slightly active cuboidal cell activity level - answer-moderatley active columnar cell activity level - answer-very active Type 1a: simple squamous cell location and function - answer-location: blood vessels and body cavities such as capillaries, alveoli function: regulates diffusion across this layer Type 1b: simple cuboidal location and function - answer-location: lines ducts such as urinary or kidney tubule function: provide moderate amounts of absorption and secretion Type 1c: simple columnar location and function - answer-location: lines intestines function: provide vast amounts of secretion and absorption (like mucus, enzymes, hormones, and nutrients) Type 1d: simple pseudostratified location and function (AKA respiratory epithelium) - answer-location: lines respiratory tract function: provides secretion and movement along surface (mainly mucus lining) Tupe 2a: stratified unkeratinized epithelium location - answer-lines internal surfaces of tubes such as the esophagus and vagina-must remain moist Type 2b: stratified keratinized epithelium location and function - answer-lines the skin prevents dehydration (keratin reduces water loss) Type 2c: transitional epithelial cells location (AKA urothelium) - answer-lines urinary bladder and ureters exocrine glands release - answer-saliva and sweat onto a surface through ducts endocrine glands release - answer-hormones into surrounding connective tissue and blood stream (no ducts) You usually become conscious of a reflex ___ it occurs - answer-After A spinal reflex is - answer-A motor response(muscle contraction) produced when a sensory neuron synapses on a spinal cord motor neuron 2 types of spinal reflexes - answer-Monosynaptic and polysynaptic (very complex) Monosynaptic reflex - answer-a sensory neuron synapses directly on cell body of a spinal cord motor neuron (only 1 synapse occurs) Polysynaptic reflex - answer--unconscious reaction to a painful stimulus -sensory neuron synapses on interneurons which synapse on motor neurons (more than 1 synapse occurs) -help you respond quickly to unexpected stimuli Are spinal reflexes slow? Fast? Are they voluntary? - answer-Very fast. Occurs before info has reached the brain. Unconscious and therefore involuntary Name the different kind of skin receptors - answer-Pain temperature touch pressure vibration. Name the muscle receptors - answer-Stretch and tension. Muscle spindles sense stretches and tension Steps in a stretch reflex (help you maintain upright posture) - answer-1. Stretch stimulates muscle spindle 2. Axons in dorsal root sends info to sensory neuron in DRG 3. Sensory neuron synapses with motor neuron 4. Axons in ventral root send info out from motor neuron 5. Contraction of muscle *BYPASSES DORSAL GRAY MATTER ALTOGETHER* The patellar tendon stretch reflex (aka knee jerk reflex). How does it work? - answer-The patellar ligament is stretched, muscle spindle receptors go through dorsal root ganglion and out through central motor neuron, quads contract and knee extends An example of a polysynaptic reflex is - answer-The withdrawal reflex What is the withdrawal reflex? - answer-An unconscious reaction to a painful stimulus. A sensory neuron synapses on inter neurons which synapse on motor neurons (more than one synapse occurs) what does the endocrine system consist of? - answer-hypothalamus, pituitary gland, adrenal gland, pancreas, pineal gland, parathyroid gland, heart, kidneys, and the thyroid gland what does your pancreatic islets do? - answer-regulates sugar levels in your body what does the hypothalamus do? - answer-master commander, releases regulatory hormones to the pituitary gland what does the posterior lobe of the pituitary gland release? - answer-oxytocin and ADH how are the endocrine and nervous systems similar? - answer-both release chemicals and share many chemical messengers 2 systems are linked through the hypothalamus and the pituitary gland how are the endocrine and nervous systems different? - answer-the nervous system releases neurotransmitters at a synapse very close to its target. fast and short project the endocrine system releases hormones into connective tissue and relies on the bloodstream to distribute its secretions far from its target cells. action is slower but lasts longer PTH and CT hormones together regulate what? - answer-regulate calcium levels whats the major difference between hormones and enzymes? - answer-hormones circulate throughout the bloodstream enzymes dont what does the endocrine system regulate and what is the goal - answer-regulates long term processes like development, growth, reproduction (and aging). regulated by negative feedback and the goal is to preserve homeostasis what are hormones? - answer-chemicals that are released from endocrine organs, are distributed by blood, and change the rate of an activity performed by the body (smooth muscle cell activity) whats homeostasis? - answer-defined as a stable internal environment. necessary for survival. body systems must function within normal range (body temp, fluid balance) how does your body maintain homeostasis? - answer-your body has receptors that sense a change in stimuli, your hypothalamus receives and processes this info from receptors and has effectors that respond with commands whats negative feedback? - answer-what kicks the homeostasis cycle into gear. the response of the effector negates the stimulus and restores normal function 3 roles of the hypothalamus - answer-as nervous tissue: controls the ANS, as the integrator between the nervous and endocrine system: secretes regulatory hormones as an endocrine organ: secretes the hormones ADH and oxytocin if the stimulus is wrong, the hypothalamus ___ - answer-sends the wrong command and homeostasis is never restored if an effector is messed up.... - answer-action won't be properly carried out blood from the hypothalamus through the pituitary gland flows___ - answer-one way-the pituitary gland has no communication with the hypothalamus the anterior lobe of pituitary gland - answer-glandular and is developed from the epithelium and is composed of endocrine cells the posterior lobe of pituitary gland - answer-developed from nervous tissue, is part of the CNS, and is composed of axons whose cell bodies are in the hypothalamus the pituitary system is composed of - answer-capillaries in both the hypothalamus and the anterior pituitary gland and is connected by portal veins in the infundibulum (stalk) advantages of the portal system - answer-allows cells in the hypothalamus to secrete very small amounts of hormones into the 1st set of capillaries allows these hormones to reach their target cells in the anterior pituitary (via second set of capillaries) very rapidly without being diluted how does the hypothalamus communicate with the anterior lobe of the pituitary gland? - answer-releasing hormones and inhibiting hormones from neurons in the hypothalamus enter blood vessels (portal system) and are released onto endocrine cells in the anterior lobe of the pituitary gland releasing hormones... - answer-stimulate secretion of hormones from the anterior pituitary (ex. GHRH) inhibiting hormones - answer-prevent secretion of hormones from the anterior pituitary (PIH inhibits prolactin secretion) FLAT (PiG) - answer-F: FSH-follicle stimulating hormone L: LH- luteinizing hormone A: ACTH- adrenocorticotropic hormone T: TSH- thyroid- stimulating hormone (FLAT) PiG - answer-P: PRL- prolactin G: GH- growth hormone theres an associated Inhibitory hormone with these the anterior lobe of the pituitary releases __ hormones - answer-6- FLAT PiG gonadotropins literal meaning - answer-gonads: ovaries, testes tropin: having an affinity for (FSH and LH) FSH - answer-stimulates follicle development in female ovaries (egg, estrogen produced here) stimulates maturation of sperm in male testes GnRH LH - answer-stimulates progesterone production (sex hormones) in females stimulates testosterone production in males GnRH ACTH - answer-stimulates the release of steroid hormones by the adrenal cortex is stimulated itself by CRH TSH - answer-thyrotropin, stimulates release of thyroid hormones from thyroid gland (basic metabolic rate) TRH secretion from the hypothalamus is controlled by? - answer-negative feedback 3 releasing hormones from the hypothalamus - answer-GnRH, CRH, TRH PRL - answer-stimulates boobie growth in females. regulated by prolactin releasing/inhibitory hormones GH - answer-stimulates growth, production caused by GHRH and GHIH PIG hormone secretions are influenced by - answer-development, age, genetics, or environmental cues (pregos) Posterior lobes of pituitary gland: - answer--Has 2 hormones:ADH (antidiuretic hormone) and Oxytocin --- that are synthesized in nerve cell bodies located in hypothalamus -released from axon terminals in posterior pituitary -taken up by bloodstream ADH - answer-antidiuretic hormone. -restricts H2O loss from the kidneys and promotes thirst oxytocin - answer-stimulates smooth muscle contractions in the mammary glands, uterus, and prostate gland where are the adrenal glands located? - answer-along the superior boarder of each kidney the adrenal cortex is (fibrous or vascular) - answer-fibrous the adrenal medulla is (fibrous or vascular) - answer-vascular the adrenal cortex synthesizes corticosteroid hormones, including - answer-mineralocorticoids, glucocorticoids, and sex steroids mineralocorticoids - answer-intended for the kidneys. increases Na+ and h2o retention glucocorticoids (cortisol) - answer-increase blood glucose sex steroids stimulate - answer-the onset of puberty (precursors to estrogen+testosterone how is the adrenal cortex stimulated? - answer-CRH released from the hypothalamus stimulates ACTH which releases from the pituitary which stimulates the adrenal glands overactive Adrenal Cortex? - answer-weight gain, high blood pressure, hyperglycemia underactive adrenal cortex - answer-addison disease, fatigue, weight loss the adrenal medullas secretory activity is controlled by the - answer-sympathetic nervous system. the adrenal medulla cells produce - answer-epinephrine (adrenaline) and norepinephrine (heart rate and blood pressure increase) iodine helps what gland function? - answer-the thyroid gland how is the thyroid gland stimulated by the hypothalamus? - answer-TRH released from the hypothalamus stimulates TSH release from the anterior pituitary which stimulates thyroxin what is the function of the thyroid gland? - answer-synthesizes T3 and T4, raises oxygen and energy consumption and heart rate/contraction strength. thyroid also contains C cells which decreases blood levels of calcium (by producing calcitonin) -raises basal metabolic rate hypothyroidism - answer-fatigue, cold intolerance, weight gain hyperthyroidism - answer-high levels of calcium. blood pressure, heart palpitations, excessive sweating, heat intolerance, and increased appetite parathyroid gland produce - answer-PTH (parathyroid hormone) causes an increase in blood levels of calcium what 2 things (within the bloodstream) are not regulated by the hypothalamus - answer-calcium and glucose the pancreas - answer--lies between spleen and small intestine -glucose regulation the pancreas contains exocrine and endocrine cells. the endocrine cells form clusters called - answer-islets of langerhans 2 major types of endocrine cells in pancreatic islets (islets of langerhans) - answer-alpha cells and beta cells alpha cells secrete ___ which ____ blood glucose while beta cells secrete ____ which _____ blood glucose - answer-glucagon, increases blood glucose, insulin decreases blood glucose insulin vs. thyroxin, cortisol, and adrenaline - answer--insulin = BUILDING hormone -thyroxin/cortisol/adrenaline = BREAKING DOWN hormones stress - answer-(this class) any condition that threatens homeostasis GAS is - answer-(general adaptation syndrome) our bodies response to continuous stress-causing factors. 3 phases 3 phases of GAS - answer-1. ALARM: fight/flight of sympathetic nervous system. dominated by epinephrine 2. RESISTANCE: dominated by glucocorticoids (fat burning stage) 3. EXHAUSTION: failure of organ systems and mineral imbalance during the resistance phase, what 3 reserves of energy does the body go through? - answer-1. glycogen reserves 2. lipid reserves (fat/fluff) 3. protien reserves (muscle) functions of the respiratory system - answer-move air to and from alveoli, provide gas exchange surface, produce sounds, and contribute to olfaction (smelll) what lines the majority of the respiratory system? - answer-a surface layer of pseudo stratified epithelium and a deep layer of connective tissue (lamina propria) Respiratory Epithelium is composed of: - answer--goblet cells (mucus) -ciliated cells (movement) -stem cells (regeneration) functions of respiratory epithelium - answer-goblet cells catches inhaled debris, cilia of ciliated cells moves mucous towards oropharynx and stem cells divide and replace old goblet and ciliated cells the nasal cavity is responsible for - answer-conchae create air turbulence and warming the air, nasal hairs filter the air, and mucous glands moisten the air the pharynx (the throat) is shared by the - answer-digestive and respiratory systems 3 divisions of the pharynx - answer-nasopharynx: contain pharyngeal tonsils and openings to auditory tubes oropharynx: contain palatine tonsils laryngopharynx: extends to opening of esophagus larynx contains: - answer-thyroid cartilage, cricoid cartilage, arytenoid cartilage, and epiglottis where is the attachment site for the vocal cords? - answer-the arytenoid cartilage/thyroid cartilage the epiglottis prevents - answer-food/liquids from entering the respiratory tract the glottis - answer--floor of larynx -entrance to trachea -composed of: vocal cords --open to breathe, closed to speak the trachea extends from the - answer-cricoid cartilage to the 1* bronchi -contains 15-20 cartilage rings (hyaline cartilage) each 1* - answer--supplies 1 lung -branch into 2* bronchi each 2* bronchi supplies - answer-1 lobe of a lung -2* bronchi branch into 3* bronchi each 3* bronchi supplies - answer-a bronchopulmonary segment of a lobe the walls of 1,2, and 3* bronchi contains progressively less - answer-cartilage and more smooth muscle the right lung has 3 lobes named _____ and separated by 2 fissures called ____ - answer-superior, middle, and inferior lobes separated by horizontal and oblique fissures the left lung has 2 lobes and is separated by 1 fissure - answer-superior and inferior lobes separated by the oblique fissure why does the left lung only have 2 lobes? - answer-the heart takes up a lot of room bronchodilation is caused by - answer-sympathetic nervous system. reduces resistance of airflow bronchioconstriction is caused by - answer-the parasympathetic nervous system. increases resistance of airflow in the lamina propria there is no cartilage, only - answer-smooth muscle and elastic fibers the bronchioles - answer--each tertiary bronchus branches into multiple bronchioles -lined by a simple epithelium -have no cartilage in lamina propria (only smooth muscle and elastic fibers) asthma - answer-excessive bronchoconstriction where does gas exchange occur? - answer-in the aveoli (in the bronchioles). 500 million per lung! aveoli is lined by what type of epithelial cells? - answer-simple squamous epithelium. type 1 cells do o2/co2 exchange type2 produces surfactant what is surfactant? - answer-an oily secretion like soap that reduces surfaces tension the connective tissue layer of the alveoli contains - answer-capillaries and elasitc fibers (NO SMOOTH MUSCLE) 3 components of respiratory membrane - answer-1. epithelial cell (type 1) lining the alveolus 2. thin layer of connective tissue in b/w 3. endothelial cell lining a capillary what happens when you have pneumonia? - answer-alveolar walls become inflamed and the alveoli become full of fluid. o2 cannot reach the bloodstream functions of the digestive system - answer-ingestion, mechanical processing, secretion, digestion, absorption, and excretion 4 major layers of the digestive tract from inside to outside - answer-mucosa, submucosa, muscularis, and serosa mucosa - answer-contains its own 3 layers: -epithelium -lamina propria (loose C.T.) -muscularis mucosae (thin, smooth muscle layer) surface epithelium in the oral cavity, pharynx, esophagus, and anus - answer-ingestion and transport. lined with stratified epithelium for protection surface epithelium along stomach, large and small intestine - answer-for digestion and absorption and rapid transport. lined with simple columnar epithelium lamina propria - answer-loose connective tissue with small blood vessels and sensory/motor nerves muscularis mucosae - answer-deep to lamina propria, a thin layer of smooth muscle. muscle contraction causes movement of mucosa submucosa - answer-deep to mucosa. dense irregular connective tissue. contains large blood vessels, lymphatic vessels, and nerves submucosal nerve plexus - answer-contains: -sensory neurons which sense chemical changes in lumen -motor neurons that innervate muscularis mucosae muscularis - answer-2 layers of smooth muscle involved in peristalsis (inner circular and outer longitudinal) and contains a nerve plexes myenteric nerve plexus - answer-senses muscle stretch and coordinates peristalsis peristalsis - answer-waves of muscular contractions that move along length of digestive tract serosa - answer-outer lining of the digestive tract. composed of simple squamous epithelium and loose connective tissue functions of the oral cavity - answer-mechanical processing (chewing), lubrication (saliva), and some digestion (amylase breaks down starch and lipase breaks down lipids) functions of the stomach - answer-storage of ingested food, sterilization of ingested food, some digestion and some absorption (alcohol and aspirin) lining of the stomach - answer-simple columnar epithelium Epithelial cells of stomach include: - answer-mucous, parietal, chief, G cells, stem mucous cells: - answer--secrete mucous for protection parietal cells: - answer--secrete HCl --gastric acid chief cells: - answer--secrete pepsinogen --converted to pepsin (when HCl and pepsinogen mix) that breaks down proteins G cells: - answer--release gastrin (stimulates secretions of parietal and chief cells) functions of the small intestine - answer-responsible for digestion and absorption of nutrients, 90% of nutrient absorption occurs in the small intestine regions of the small intestine - answer-duodenum, jejunum, ileum what does the duodenum receive from the stomach and pancreas/liver? - answer-begins at pyloric sphincter -it receives chyme from the stomach and enzymes and buffers from the pancreas and liver what pH level is in the duodenum? - answer-neutral where does most digestion and absorption occur? - answer-jejunum ileum - answer-ends at ileocecal valve -controls flow from small intestine to large plicae (small intestine) - answer-fold in the intestinal lining to increase surface area villi (small intestine) - answer-fingerlike projections to increase surface area what are all of the epithelial cells lining the small intestine? - answer-Absorptive cells, goblet cells, CCK (cholecystokinin secreted from gallbladder), S cells (secrete secretin), GIP cells (secrete gastric inhibitory peptide), and stem cells functions of the large intestine - answer-absorption of water and vitamins, and compacts feces/stores feces prior to defecation regions of large intestine - answer-cecum, colon, rectum cecum - answer-receive material arriving from ileum appendix - answer--attached to cecum -lymphoid organ regions of the colon - answer-ascending, transverse, descending, sigmoid ascending colon - answer--begins at the cecum -goes up along right side of belly transverse colon - answer--crosses belly from right to left descending colon - answer--goes down on left side of belly sigmoid colon - answer--s shaped segment -empties into rectum epithelial cells lining colon - answer-goblet (main) and absorptive does the colon contain villi? - answer-no what lines the anus? - answer-stratified squamous keratinized epithelium the exocrine pancreas - answer---exocrine cells: -99% of pancreatic cells -secrete pancreatic enzymes into ducts pancreatic enzymes - answer-1. amylase -breaks down carbs into di and tri saccharides 2. lipase -breaks down lipids into fatty acids 3. proteases -breaks down proteins into peptides the liver - answer--largest visceral organ -divides into lobes: right, left, caudate, quadrate what does the inferior vena cava (within the liver) do? - answer-takes blood back to the heart functions of the liver - answer-removes and stores nutrients and toxins from the blood, synthesizes nutrients when necessary, regulates blood glucose, lipid, amino acid levels, phagocytes(retires) old RBC's, synthesizes bile blood drains out of the liver via - answer-hepatic veins into the inferior vena cava bile drains out of the liver via - answer-hepatic ducts and onto the gall bladder why is bile important? - answer-bile helps digest fats how does the gall bladder get rid of bile? - answer-the gall bladder contracts, releasing bile via the common bile duct into the duodenum through the duodenal papilla