Biol 224 Exam 3 Endocrine

What is a hormone?
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Where do hormones produce effects?only in the target cell that has a receptor for the hormoneHow are hormones removed?by destruction of elimination -freely circulating hormones are rapidly removed from blood -hormones bound to transport proteins remove more slowlyDoes thyroid hormone have a cholesterol base? ExplainNO, no it acts like a lipid and the receptors are inside the cellWhat are amines?amino acid derivatives of hormones such as epinephrine, norepinephrine, thyroid hormones etcWhat are peptide hormones?chains of amino acids -insulin, glucagon, growth hormone etc -move freely through the body and bind to the cell membraneWhat are lipid derivative hormones?steroid structurally related to cholesterol -estrogen, testosterone and aldosterone -cholicalciferol aka vitamin DWhat is melatonin?an amino acid derivative and a derivative of tryptophan that is secreted by the pineal glandWhat is thyroxine?an amino acid derivative and a derivative of tyrosine secreted by the thyroid glandDoes thyroid hormone have a cholesterol base?noWhat are epinephrine and norepinephrine?an amino acid derivative and a derivative of tyrosine (catecholamines) secreted by the adrenal medullaWhat is dopamine?an amino acid derivative and a derivative of tyrosine (catecholamines) secreted by the hypothalamusExplain thyroid hormoneamino acid derivative -pretends its a lipid -receptors inside cellHow do hormones effect target cells?-gene activation leading to synthesis of an enzyme or protein -increasing or decreasing rate of synthesis -turn an enzyme on or offWhat receptors are in the cell membrane and why are they there?-on membrane because hormone cannot cross cell membrane -amines, peptimes, eicosanoids - not a hormomeWhat do hormones do?change biochemical activity in cellWhat is an example of hormonal gene activation?insulin being released in response to high blood sugar to bring it downwhat does hormone gene activation do?leads to the synthesis of an enzyme or protein -increases of decreases the rate in which they are made -can turn an enzymes on or offwhere do amines and peptide hormones bind?to the cell membrane which then activates g protein which activates the enzyme which activates cyclic AMP or calcium ionsWhat is the 2nd messenger?cyclic AMP or calcium ionsExplain what happens when a hormone has a cell membrane receptorthe hormone is released from the blood and attaches to a specific cell membrane receptor which then activates the g protein which then cause Ca channels to opn or cycclic AMP to enter which then acts as the 2nd messenger for the cellDo thyroid and steroid hormones cross cell membranes?YESWhy do thyroid and steroid hormones enter the cytoplasm or nucleus?because they are lipid solubleWhat do thyroid and steroid hormones do once inside the cell?produce effect by controlling gene expression and ATP synthesisWhen a peptide hormone binds to receptors on the surface of a cell: A) the hormone receptor complex moves into the cytoplasm B) the cell membrane becomes hyper polarized C) 2nd messenger is produced or removed from the membrane D) the hormone is transported to the nucleus where it alters the activity of DNAC 2nd messenger is produced or removed from the membraneexplain increased cAMP levelshormones bind (epinephrine and norepinephrine BETA receptors, calcitonin, parathyroid hormone, ADH, ACTH, FSH, LH, TSH, glucagon) which then acts on the g protein. adeylate cyclase, which along with ATP then acts on the 2nd messenger cAMP which activates kinase which opens ion channels and activates enzymesexplain decreased cAMP levelshormones bind (epinephrine and norepinephrine ALPHA receptors) which then acts on the g protein. and inhibits adeylate cyclase via PDE, which breaks down cAMPExplain Ca2+ levelshormone attaches to membrane receptor which activates the g protein which activates phosohlipase c which releases stored Ca and activates PKG which opens Ca channels and then ca binds to calmodulin which activates enzymes -hormones that make this happen include epinephrine and norepinephrine ALPHA receptors, oxytocin, regulatory hormones of the hypothalamus and eicosanoidsExplain what happens when steroid hormone enters the cellenters the cell, attaches to receptor in cytoplasm or nucleus, activates gene, transcription and mRNA production happen, translation and protein synthesis happen and then the target cell respondsExplain what happens when thyroid hormone enters the cellenters the cell, attaches to receptor in mitochondria or nucleus, activates gene, transcription and mRNA production happen, translation and protein synthesis happen and then the target cell responds, in mitchondria causes increased ATP production and a target cell responsewhat is reflex control in endocrine activity?a negative feedback control mechanism -response to cahnges in fluid or blood -location of recepto may be in gland or hypothalamuswhat are simple endocrine reflexes?direct effect on gland secreting the hormone. such as glucose levels in blood control insulin release by endocrine cells in pancreaswhat are normal levels of glucose?70-110 mg/dLWhat happens when blood sugar drops?alpha cells of the pancreas secrete glucagon which causes increased breakdown of glycogen to glucose from the liver and skeletal muscle, increased breakdown of fats and fatty acids, from adipose tisse, and increased synthesis and release of glucose from the liver, which cause thes blood glucose to rise and return to normal levelswhat happens when blood sugar rises?beta cells in the pancreas secrete insulin which causes increased rae if glucose into target cells, increased rate of glucose use and ATP generation, increased conversion of glucose to glycogen in the liver and skeltal muscle, increased amino acid absorption and protein synthesis and increased triglyceride synthesis in the adipose tissue, this cause blood glucose levels to drop and go to normal levelsWhat are complex endocrine reflexes?indirect effects which involve the hypothalamus, pituitary gland and 2 or more hormones such as thyroid levels controling release of TRH by hypothalamus, TRH levels control TSH by pititary gland and TSH levels control thyroid gland secretion of thyroid hormoneWhat are tropic hormones?from the pituitary gland that don't have a direct effect on the target cell, cause another gland to produce a hormoneWhat do high levels of TSH indicate?that there is low t3 and t4 or the thyroid not producingWhat happens with the TRH, TSH, thyroid hormone cycle?TRH released from hypothalamus which goes into blood and then to receptor on pituitary gland that releases TSH into blood which then binds to receptor on the thyroid gland which then releases thyroid hormone T3 or T4Whewhat is the neurohypopphysis?the posterior portion of the pituitary gland developed as an outgrowth of the CNSwhat is the adenohypopphysis?the anterior portion of the pituitary gland developed as an outgrowth of the glandular tissue of the pharynxHow many peptide hormones does the pituitary gland release?9, all 9 bind to membrane receptors and use cAMP or Ca2+ as a 2nd messengerwhat controls hormone release of the adenihypophysis?thyroid hormones from the hypothalamuswhat is thyroid stimulating hormone? (TSH)aka thyrotropin it triggers the release of hormones from the thyroid gland -released by TRHWhat is thyrotropin releasing hormone? TRHfrom the hypothalamus promotes the release of TSHWhat is adrenocorticotropic hormone? ACTHaka corticotrpin it stimulates the release of glucocorticoids from the adrenal coretex -corticotropin releasing hormone (CPH) from the hypothalamus causes the secretion of ACTHWhat does corticotropin releasing hormoine do?comes from the hypothalamus and trigers ACTH secretionWhat does the hypothalamus do?lots of releasing, has receptors for thyroid hormone when levels drop it signals the anterior pituitarywhat are gonadotropins?from the adenohypopphysis, FSH and LHWhat is follicle stimulating hormone? (FSH)a gonadotropin from the adenohypopphysis that stimulates follicle development aka egg maturation and stimulates sperm production in the sustentacular cells of the testesWhat is luteinizing hormone? (LH)a gonadotropin from the adenohypopphysis that cause ovulation and progestin production in ovaries and causes androgen production in testesWhat is gonadotropin releasing hormone? GnRHGnRH from hypothalamus promotes secretion of FSH and LH -not reached until puberty -also requires leptin which means proper nourishmentif there are peaks is FSH in females what else are there peaks of?estrogenWhat is prolactin?from the adenohypopphysis stimulates the developement of mammary glands and milk production -some in placenta -causes glands to fill with milk but oxytocin needed for milk to be releasedwhat is melanocyte stimulating hormone? MSHstimulates melanocyes to produce melanin pigment in skin and other locations -trace amounts in humans -produced by pituitary glandWhat is growth hormone? GHaka somatotropin -causes release of somatomedins from liver which cause and increase in amino acid uptake in skeltal muscle, cartilage, stimulate portein synthesis and cell growth -directly effects increased cell division in epitheelial and connective tissue, enhance breakdown of lipid and glycogen reserves -released caused by GHRH and GH inhibitinh hormone from hypothalamusWhat is an example of what growth hormone does?lifting weights, muscle cell enlarge, transciption, translation, more myofibrils which are stimulated by stomatomedinWhat does a growth hormone supplement do?divides and breaks down bonesWhat are inhibatory hormones?involved with all hormones but play a very little role, just keep hormone levels in checkWhat is the neurohypopphysis?posterior lobe of the pituitary gland -contains axon terminals of the hypothalamic nerve cells that secrete hormones into the bloodWhat is antidiuretic hormone ADH?decreases the amount of water lost at the kidneys, drecreases urine production -elevates blood pressure -axon receptors in kidneys -water moves from tubules into blood stream -dehydration decreased blood pressureWhat is oxytocin?stimualtes contractile cells in mammary glands -causes contractiions in delivery -simulates smooth muscle in uterus -cuddle horomone -orgasmsexplain what happens when you break the seal when drinking?alcohol surpresses the release of ADH thus more water is releasedWhat is the thyroid gland?-c cells (parafollicular cells) which produce calcitonin in response to to increased calcium levels -calcitonin inhibits osteoclasts and increase Ca excretion by kidneys -follicle cells which release thyroid hormones -thyroxine T4 -triiodothyronine T3What are follicle cells?-release thyroid hormones -thyroxine (T4) inactive -triiodothyronine (t3) activeWhat are thyroid hormones?amino acids with attached iodide ions -90% of excretions are T4 with 4 iodid ions -T4 is converted to T3 by enzymes in peripheral tissues -T3 is the active form of the hormone, T4 is inactive -synthesis and release of thyroid hormones is controlled by TSH in the hypothalamus -hypothalamus only recognizes T4 -thyroid hormone prentends its a lipidWhat are the functions of thyroid hormones?increase metabolism -cross cell membranes and bind to intracellular receptors -bind to mitchondria and increase rate of ATP ptoduction -bind to receptors that activate genes that control energy useWhat is cretinism?low thyroic in childood, catastrophic because it controls developement of skeletal muscular and nervous sytems -larger in childhoodWhy is the thyroid important in adulthood?controlling metabolismWhat is hypothyroidism?low body tempWhat is hyperthyroidism?high body temp, heart damage, increased HR,increased BPwhat is goiter?enlarged thyroid, happens in landlocked places because there is not enough iodide, -keeps making amino with no end -low T3 and T4 so TSH goes up and stimulate itWhat are parathyrpid glands?4 glands in posterior o thyroid gland -secrete parathyroid hormone PTHWhat is parathyroid hormomeoppostie of calcitonin -responds to low calcium -PTH increased calcium levels by stimulating osteoclasts, inhibiting osteoblasts, decreasing ca excretion by kidneys stimulating formation of calcitrol by kidneysWhy are calcium levels so important?because they effect: -nerve and muscle cell excitability -maintained by negative feedback system from PTH and calcitoni -PTH and calcitonin have opposing effects -bones osteoclasts and blasts -digestive tract absorb ca -calcitriol -kidneys excrete calcium ionsWhat is the adrenal gland?sits on kidneys, made of adrenal medulla inner level and adrenal cortex outer levelWhat is the adrenal medulla?neuroendocrine cells that secrete epinephrine and norepinephrine -rush into blood stream, sympathetic full body response -secretes 75-80% epi and 20-25% norepi -produce increased availbility of energy resources -cause breakdown of glycogen in liver to release glucose for brain use -cause breakdown of fat to release fatty acids for use by other cells of body -produce increased rate of force for cardiac contractions and other symptahtic effects -controlled by ANS activityWhat is the adrenal cortex?-secretes steroid hormones (coticosteroids) -mineralocorticoids -aldesterone -secreted if Na is low and K is high or BP is low, cause rentention of Na and water and loss of K -glucocorticoids - secreted in response to ACTH release from adenohypophysis cause decrease use of glucose and increase glycogen stores, antiinflammatory effcts -androgens - encourages bone and muscle growth and blood formation, primary role is in womena dn children and testes in mae produces larger amountsmineralocorticoids -aldesterone effect what?the kidneys sweat, sailvary glands and pancreas causing electrolyte compostion and increase rentetion of Na and water and loss of Kglucocorticoids effect what?in most cells and release amino acidsand lipids to promote glucose and glycogen from liver , antiinflammatoryandrogens effect what?women and children and encourages bone and muscles growth and blood formationWhat does the pineal gland do?secretes melatonin -increased sun causes decreased melatonin secretion -set circadian rythyms -antioxidant pritecting free radical damage -inhibiting reproductive functionWhat is seasonal affective disorder?depression correlated with decreased sunlight exposure and increased melatoninWhat is the pancreas?99% is excrine cells that secrete enzymes into digestive tract -endocrine cells in small clusters that edal with blood glucoseWhat do alpha pancreatic cells do?secrete glucagon in respinse to low blood sugarWhat do beta pancreatic cells dosecrete insulin in response to high blood sugarWhat is insulin?secreted by beta pancreatic cells -increases rate of glucose uptake and use in insulin dependent cells -increased uptake of fatty acidss and synthesis of triglycerides in adipose cells -increased uptake of amino acids and synthesis of proteinsWhat is glucagon?secreted by alpha cells of pancreas -increaseds glycogen breakdown -in liver glucose is then released unto blood, inmusce glucose remains -increases gluccose made by amni acids in liver -increased release of fatty acids into blood -glucose sparing, most cells start to us FA as energy source instrad of glucoseWhat is diabetes insipidus?polyuria - increased urine production -inadequate ADH secretionWhat is diabetes mellitus?polyuria- excess urine -glycosuria - glucose in urine -hyperglycemia-high blood glucose -breakdown of lipids and proteins as energy source for cell metabolism - ketone bodies -ketoacidosisWhat is type 1 diabetes?insulin dependent, inadequate insulin production, geneticWhat is type 2 diabetes?non insulin deoendent -inadequate insulin receptor respinse, not geneticWhat are the endocrine tissues found in adipose tissue?leptin - feedback control for appetite resistin - reduces insukin sensitvityWhat are the endocrine tissues found in thymus?thymosins -regulate immune responsesWhat are the endocrine tissues found in intestines?coordinate digestive activitiesWhat are the endocrine tissues found in gonads?ovaries and testes secrete hormones involved in reproductive functionsWhat are the endocrine tissues found in kidneys?hormones regulaing blood volume, blood pressure and blood calcium levelsWhat are the muscles of the digestive tract?oral cavity, stomach, pharynx, esophagus, small intestine, large intestineWhat are the accessory organs of the digestive system?salivary gands, pancreas, liver and gallbladderWhat are the functions of the digestive system?ingestion, mechanical processing, digestion, secretion, absorption and excretionWhat are the muscular layers of the diestive tract?-mucosa -inner most layer with many exo and endocrine gland cells, epithelia replaces rapidly by stem cells, provides protection, secretion and absorption -submucosa - layer of dense irregular connective tissue that provides structure and strength, blood and lymoh vessels collectand carry absorbed nutrients from capillaries to mucosa layer -muscularis layer - smooth muscle thats the outer longitudinal layer and inner circular kayer and 3rd layer on stomach as obique, mechanically processes and moves, movement cooridnated by ANS enteric nervous syetem, hormiones and local factors -adventitia - outer ayer that covers muscularis or oral cavity esophogus and rectum, connects firmly to adjacent body wall -serosa - covers muscularis of all parts of GI tract that are free to move, mesetaries re extensions that connect to body wallWhat is the enteric nervous system?sensory neurons, motor neurons and interneurons, -myenteric plexus-between longitudinal and cicular muscle layers -submucosal plexus - between submucosal and muscularis muscle layers -input from parasympathetic and sympathetic ANS -ACh speeds up digestions -digestion is a reflexDo you start digestion before your brain is involved?yesWhat is visceral smooth muscle?-interconnected by gap junctions -pacesetter cells initiat rythymWhat does it mean that histamine is a local factor?it is a paracrine secretion and secreted from nearby mast cells so it doesn't require blood flowWhat does pepsid do?blocks histamine receptorsWhat does gastrin do?stimulates digestionWhat does epinepherine do in the stomach?inhibits itWhat do ANS long reflexes do?controls large areasGI activity is _____ by parasympathetic activitystimulatedGI activity is _____ by sympathetic activityinhibitedWhy do puppies poop right after eating a meal?because their long reflex is stimulated which causes the whoe GI tract to be stiumlated causing peristalsis which pushes the previous meal outWhat are short reflexes?localized responses -control within the enteric nervous systemWhat is segmentation?the churn and fragment a bolus of digestive contents mixing in with intestinal secretionsWhat is peristalsis?waves that move a bolus down the length of the tractWhat are the functions of the oral cavity?-analysis of material - is it spoiled or poison? -mastication - mechanical processing -lubrication via salivary -initial digestion of starch and lipids with salivary amylase and lingual lipase -prevent entry of pathogens - palantine, lingual and parotid tonsilswhat are your 3 salivary glands and how much saliva do they produce?parotid - 25% sublungual - 5% submandibular - 70%What are the functions of saliva?moisten food -glycoproteins (mucins) for lubrication -buffers to maintain neutral pH -antiboidies (IgA) and lysosomes to fight bacteria -salivary amylase to initiate digestion of starch and ligual lipase for lipidsWhat is your pharynx?the common passageway for food, liquids and air -connect trachea and esophagus -pharyngeal skeletal muscles assist in swallowingWhat is your esophagus?carries solids and liquids from pharynx to stomach -skeletal and smooth muscle -upper and lower esophageal areasWhat are the 3 phases of swallowing?buccal phase - voluntary, tongues moves bolus into pharynx, soft palate uvula elevate to close of nasopharynx -pharyngeal phase - involuntary control via swallowing center, elevate larynx and close epiglottis, breathing stops momentarily -phayngeal constrictor muscles move bolus down into esophagus -esophageal phase - involuntary control via swallowing center -peristalsis moves bolus down, lower esophageal sphincter opens and food enters stomachWhat would happen if your esophagus was open all the time?you'd burp all the timeWhat do g cells do?secrete gastrin hormone, which stimulates digestionwhat do chief cells do?secrete pepsinogen, which is inactive, which is converted to pepsin by stomach acid HCLwhat do parietal cells do?responsible for HClwhat is absorbed in the stomach?alcohol and aspirinwhat do drugs like prilosec and prevacid do?they are a proton pump inhibitor and disables H ion and ATPase transport protein to prevent heart burnWhat do drugs like tagamet and zantac do?they are a histamine and H2 antagonists that block parental cellswhat happens in the gastric phase of digestion?digestion is stimulated by stressing of stomach and ph increase and undigested protein -gastrin has to be circulated through the blood since it is a hormone -food in stomach for 3-4 hoursWhat happens in the intestinal phase of digestion?small squirts of chyme leave via the pyloric sphincter -inhibit gastric gland cells -inhibit stomach wall muscles -caused by stretching of intestinal walls, ph decrease in intestines and undigested lipids and carbohydrates -move chyme towards colon via peristalsisWhat is a gastric ulcer?responsible for 80% of stomach ulcer -h pylori breaks alkaline mucous then cells are exposed to stomach acidsWhat is gastric bypass?large portion of the stomach and duodenum are bypassedWhat is stomach banding?limiting how much food can go into the stomach and can be adjusted over timeWhat happens in the small intestine?chemical digestion is completed -enzymes from intestinal glands -enzymes from pancreas -bile salts from the liver -nutrients are absorbed -peristalsis still moving chyme towards the colonExplain the small intestine physicallymuscular tube that is 20ft long made up of the duodenum 10 inches, the jejunum, 8 ft pond and the ileum which is 12 feet longWhat connects the stomach and the small intestine?the pyloric sphincterwhat connects the small and large intestines?the ileocecal sphincterWhat does the pancreas releases?alkaline buffers to raise the ph of chyme, and enzymes such as pancreatic amylase and pancreatic lipase -as well as endocrine factor like insulin and glucagonWhat does pancreatic amylase do?breaks down starch to disaccharidesWhat does pancreatic lipase do>?breaks down lipids into fatty acidsWhat do nucleases do?break down nucleic acids into nucleotidesWhat do proteolytic enzymes like proteases and peptidases do?break down proteins into polypeptides into amino acidsWhat do bile salts do? Where do the come from?help emulsify lipids -come from the liver and the gallbladderWhat is bilirubin?a waste product from the heme of RBCs recycled in the liver and gives urine and feces there color, too much can cause jaundice which can cause neural damageWhat is the gallbladder?muscualr expandable sack that stores bile produced by the liver -shares the common bile duct with the liver and connect to the duodenum -hepatopancreatic sphincter controls the release of both pancreatic solutions and bileExplain the general process of digestion from the mouth through the small intestinefood enters the mouth where it meets some enzymes that start digesting things like carbs such as salivary amylase the food then travels down the esophagus down to the stomach where HCl is released onto it an it becomes very acidic, the little chunks of it are pushed out of the pyloric sphincter once its in the small intestine the liver and gallbladder release bile salts onto it and the pancreas real ease enzymes to further break it down then when it gets into the jejunum it reaches the brush border where it is broken down even further after more enzymes are released and then it is carried across the cells and into the blood streamWhat are the hormones secreted by the duodenum?CCK and SecretinWhat does CCK do? Where is it secreted?secreted in the duodenum -released in response to not fully digested food -inhibits stomach secretions and mobility -stimulates secretions of pancreatic enzymes stimulates contraction of gallbladder -stimulates relaxation of hepatopancreatic sphincterWhat does secretin do?secreted in duodenum -more involved in the ph side of things -released in response to acidic s=chyme -inhibitys stomach secretions and motiloty -stimulates pancreas to release buffers -stimulates lvier to increase bile secretionWhat would increased parasympathetic stimulation to the intestine do?speed everything up, ACh being deliveredWhat is a long reflex?wide spread reflex, vagus nerve and the whole GI tract is stimulatedWhat is the large intestine?muscular tube about 5 ft long and 3 inches in diameter made up of the cecum and the appendix, the colon and the rectumAre there villi in the large intestine?noAre there any digestive enzymes produced in the large intestine?noWhat do bacteria manufacture in the large intestine?vitmain k, biotin and vitmain b5What is absorbed in the large intestine?lots of stuff! -water -vitmains -biles salts -organic wastes and toxins -ammonia is converted to uria