| Question | Answer |
| multistep steroid synthesis pathway, of adrenal cortex, starts with | cholesterol |
| insulin is a(n) __ hormone | hypoglycemic |
| __ __ of cortisol occur in evening just before and shortly after we fall asleep | lowest levels |
| alcohol intake inhibits the secretion of ADH, thus the absence of ADH there is | increased urine output |
| also act locally but affect cell types other than those releasing the chemicals | paracrines |
| basic mechanism of glucocorticoid action on target cells is to | modify gene activity |
| in some instances aldosterone's effect on distal kidney tubules can alter __ balance of blood by H+ excretion | acid-base |
| any hyperglycemia hormone called into action as blood glucose levels drop __ __ insulin release by promoting glucose entry into bloodstream | indirectly stimulates |
| within a negative feedback system the target organ effects | inhibit further hormone release |
| loss of sensation, muscle twitches, & convulsions | tetany |
| homeostatic imbalance of Grave's disease would be due to the hormone deficiency/overproduction of | hypersecretion of thyroid hormone |
| GH | mobilizes fats, spares glucose, and promotes the protein synthesis necessary for growth |
| hormone that enhances carrier-mediated diffusion of glucose into tissue cells, thus lowering blood glucose levels; small protein consisting of 2 amino acid chains linked by disulfide bonds | insulin |
| gland located behind stomach, between spleen & duodenum; produces both endocrine & exocrine secretions | pancreas |
| binding of thyroid-stimulating hormone promotes synthesis of thyroid hormone | thyroxine |
| IGFs produced by __ act as hormones | liver |
| triggers thyrotrophs to release TSH | thyrotropin-releasing hormone (TRH) |
| testes produce | testosterone |
| bone-reabsorbing cells | osteoclast |
| posterior pituitary is a(n) __ area | hormone-storage |
| glucocorticoids are adrenal cortex hormones that | increase blood glucose levels and aid the body in resisting long-term stressors |
| formed largely by cubiodal or squamous epithelial cells & produce glycoprotein thyrogolubulin | follicle cells |
| lead to changes in blood volume & blood pressure | changes in Na+ blood concentration |
| receptors for ACTH are normally found on certain cell of | adrenal cortex |
| sympathetic nervous system stimulation of adrenal medulla to release catecholamines during periods of stress | example of neural stimuli |
| hormone secreted by heart when blood pressure rises; fine-tunes blood pressure & sodium-water balance of body | atrial natriuretic peptide (ANP) |
| are found in walls of small intestine, stomach, kidneys, & heart | hormone-producing cells |
| enteroendocrine cells are sometimes referred to as __ because they are similar in certain ways to neurons & many of their hormones & paracrines are chemically identical to neurotransmitters | paraneurons |
| any given hormone will influence the activity of | its target cell |
| because of many variations, hormonal __ __ must be precisely & individually controlled to meet continuously changing needs of body | blood levels |
| once activated (cAMP) G protein behaves like a light switch, off when __ is bound to it and on when __ is bound | GDP; GTP |
| calcitonin has an antagonizing effect on __ hormone | parathyroid |
| sympathetic nervous system stimulation & rising amino acid levels are also __ for glucagon release | stimulatory |
| calcitonin has a __ effect | bone-sparing |
| hormones influence number & affinity not only of their own receptors but also receptor that | respond to other hormones |
| PTH release is triggered by __ blood Ca2+ levels | falling |
| catecholamines cause relatively __ responses to stressors | brief |
| glucagon-synthesizing cells of pancreas | alpha cells |
| G protein that inhibits adenylate cyclase | Gi |
| function of erythropoietin | increases red blood cell production |
| amber-colored, sticky substance in the thyroid gland containing thyroglobulin protein with attached iodine atoms | colloid |
| simple amino acid derivatives | amines & thyroxine |
| rare & usually results from tumor; calcium is leached from bones causing bones to soften & deform as their mineral salts are replaced by fibrous connective tissue | hyperparathyroidism |
| because __ activates some proteins and inhibits others (during cAMP) a variety of processes may be affected in same target cell at same time | phosphorylation |
| GH is produced by cells called | somatotrophs |
| sets the resting membrane potential of cells & determine how easily action potentials are generated in nerve & muscle | extracellular contractions of K+ |
| in certain instances, any of second messengers & hormone receptor itself can cause changes in | intracellular Ca2+ levels |
| steroid hormones enter cell & form DNA/hormone complex before they | change cellular function |
| reproduction; growth & development; maintenance of electrolyte, water, & nutrient balance of blood; regulation of cellular metabolism & energy balance; & mobilization of body defenses | major processes controlled & integrated by endocrine system |
| urine production | diuresis |
| excessive hunger & food consumption | polyphagia |
| when hypothalamic-hypophyseal tract neurons fire they release the stored hormones into a capillary bed in __ pituitary for distribution throughout the body | posterior |
| protrusion of eyeballs, if tissue behind eyes becomes edematous & then fibrous; common in Grave's disease | exophthalmos |
| aldosterone is the most __ mineralocorticoid | potent |
| innermost cells abutting adrenal medulla in netlike arrangement; mainly produce small amounts of gonadocorticoids | zona reticularis |
| in both sexes FSH stimulates __ production | gamete |
| ACTH levels peak in | morning shortly before awakening |
| in order for target cell to respond to hormone, cell must have __ __ receptors on its plasma membrane or in it interior to which that hormones can bind | specific protein |
| all major hormones circulate to __ __ tissues | virtually all |
| pancreatic islets are also know as | islets of Langerhans |
| cortisol blood levels peak __ __ we arise in morning | shortly before |
| hypothalamic regulatory hormones can be a(n) | single amine to peptides to proteins |
| cortisol, cortisone, corticosterone | glucocorticoid hormones |
| each adrenal glands is structurally & functionally | two endocrine glands |
| 2 DITs result in | T4 |
| ketones begin to spill into the urine | ketonuria |
| decrease blood pressure by allowing Na+ (and water_ to flow out of body in urine | ANP mechanism's overall influence |
| made primarily by paraventricular neurons of hypothalamic-hypophyseal tract | oxytocin |
| low blood Ca2+ levels | hypocalcemia |
| PTH release is inhibited by __ blood Ca2+ levels | rising |
| permissiveness is the property in which a hormone __ __ its full effect without another hormone | CANNOT exhibit |
| hormones are __ __ the extracellular fluids | secreted into |
| renin-angiotensin, plasma concentrations of K+, ACTH, & atrial natriuretic peptide (ANP) | mechanisms that regulate aldosterone secretion |
| most hormones can be __ __ as either amino-acid based/steroids | classified chemically |
| made primarily by supraoptic neurons of hypothalamic-hypophyseal tract | antidiuretic hormone (ADH) |
| 90-110mg/100ml of blood is the __ range of glucose levels in the blood | normal |
| when thyroglobulin is synthesized and discharged into follicle lumen | step 1 synthesis of TH by follicle cells |
| cyclic AMP activate protein kinase | 5th step of cAMP mechanism |
| after glucose enters target cell, insulin binding triggers enzymatic activities that join glucose molecules together to | form glycogen |
| receptor activates G protein | 2nd step of cAMP mechanism |
| hormonal stimulus typically activates or deactivates __ | enzymes |
| persistent elevated blood glucose levels brought on by pharmacological doses of glucocorticoids | steroid diabetes |
| iodine-containing hormone secreted by the thyroid gland; accelerates cellular metabolic rate in most body tissues; major hormone secreted by thyroid follicles | thyroxine (T4) |
| the elevation blood glucose levels that occurs when GH acts upon liver brings about the __ __ or anti-insulin effect of GH | glucose sparing |
| as body cells take up glucose & other nutrients, and plasma levels of these substances drop, insulin secretion | is suppressed |
| rising levels of GH feed back to also __ its own release | inhibit |
| for steroid & thyroid hormones, in absence of hormone receptors are bound up in | receptor-chaperonin complexes |
| excessive growth of the body or any of its parts, especially as a result of oversecretion of the growth hormone by the pituitary gland | gigantism |
| phosphatidyl inositol bisphosphate | PIP2 |
| humoral stimuli are __ endocrine controls | simplest |
| condition resulting from underactive thyroid gland in adults | myxedema |
| adrenocorticotropic hormone (ACTH) also called | corticotropin |
| function of oxytocin | increases contraction of uterine smooth muscles |
| excessive blood levels of Ca2+ (approx. 20% above normal) act as a __ stimulus for calcitonin release | humoral |
| anterior pituitary hormone that aids maturation of cells in the ovary and triggers ovulation in females; in males, causes the interstitial cells of the testis to produce testosterone | luteinizing hormone (LH) |
| hypothalamus __ __ of the pituitary gland | regulates activity |
| after glucose enters target cell, insulin binding triggers enzymatic activities that catalyze __ of glucose for ATP production | oxidation |
| lipid-soluble hormones include | steroid & thyroid hormones |
| organ that produces TSH | anterior pituitary (adenohypophysis) |
| pancreatic beta cells are stimulated to secrete insulin by release of acetylcholine by __ nerve fibers | parasympathetic |
| epinephrine is used clinically as heart stimulant & to dilate bronchioles during | acute asthmatic attack |
| calcitonin is produced by | parafollicular / C cells |
| composed of 9 amino acids; differ in only 2 amino acids | ADH & oxytocin |
| if K+ loss is __ neurons become nonresponsive & muscle weakness (eventually paralysis) occurs | extreme |
| temporary endocrine organ; secretes several steroid & protein hormones that influence course of pregnancy | placenta |
| stalk of tissue that connects the pituitary gland to the hypothalamus superiorly | infundibulum |
| excessive insulin secretion | hyperinsulinism |
| depends on type of target cell, specific protein kinase it contain, & substrates within that cell available for phosphorylation by protein kinase | sequence of reaction set into motion by cAMP |
| circulating insulin lowers blood glucose levels by inhibiting __ of glycogen to glucose | breakdown |
| thyroglobulin colloid is endocystosed; follicle cells must reclaim iodinated thyroglobulin by endocytosis & combine vesicles with lysosomes | step 6 synthesis of TH by follicle cells |
| function of thyroid-stimulating hormone | stimulates production of thyroxine |
| unusual arrangement of blood vessels in which a capillary bed feeds into veins, which in turn feed into another capillary bed | portal system |
| estrogen stimulates prolactin release | directly & indirectly |
| GH has a daily cycle with the highest levels occurring during | evening sleep |
| glia-like supporting cells | pituicytes |
| POMC is a __ for ACTH | prohormone |
| hormones that are derived from __ are called steroids | cholesterol |
| __ hormones exhibit shorted half-lives | water-soluble |
| hormonal stimulus typically alters plasma membrane permeability/potential (or both) by | opening/closing ion channels |
| rising levels of TH feed back to __ hypothalamic-anterior pituitary axis, temporarily shutting off stimulus for TH release | inhibit |
| veins leaving pituitary drain into | dural sinuses |
| gland/organ that produces glucocorticoids | adrenal cortex |
| some T4 cane be converted to T3 __ secretion | before |
| GH promotes protein __ | synthesis |
| iodination of thyroid hormones is mediated by | peroxidase enzymes |
| produced in response to the gonadotropins, feed back to suppress FSH & LH | gonadal hormones |
| anterior pituitary hormone that stimulates adrenal cortex to release corticosteroid hormones | adrenocorticotropic hormone (ACTH) |
| steroid hormone of adrenal cortex that regulates Na^+ & K^+ metabolism & fluid balance | mineralocorticoids |
| spherical cell that stains readily with chromium salts, especially a cell of the adrenal medulla | chromaffin cells |
| thymulin, thymopoietins, & thymosins are called hormones but they | mainly act as paracrines |
| abnormally elevated blood Ca2+ levels | hypercalcemia |
| cells of anterior pituitary that release TSH | thyrotrophs |
| ACTH | stimulate adrenal cortex |
| regulation of blood levels of TH is on a(n) | negative feedback loop |
| in both sexes, produced by hypothalamus, gondaotropin release by anterior pituitary is promoted by | gonadotropin-releasing hormone (GnRH) |
| pituitary gland is also known as | hypophysis |
| T3 that binds to target tissue receptors does so | much more avidly & is about 10x more active |
| rheumatoid arthritis & allergic reactions use __ __ to control symptoms of chronic inflammatory disorders | glucocorticoid drugs |
| category of hormone of cortisol | glucocorticoids |
| when TSH from anterior pituitary binds to receptors on thyroid follicle cells, first response is to | secrete stored thyroid hormone |
| three plasma membrane components to determine intracellular levels of cAMP | hormone receptor, G protein, & effector enzyme |
| pancreatic beta cells are stimulated to secrete insulin chiefly by | elevated blood glucose levels |
| IGFs stimulate actions required for growth by uptake of nutrients from blood & their incorporation into proteins & DNA allowing growth by | cell division |
| category of hormone of FSH & LH | gonadotropins |
| receptors are __ structures | dynamic |
| adrenal sex hormones | gonadocorticoids |
| the rate of steroid hormone release in response to stimulation depends on their | rate of synthesis |
| calcitrol is __ __ of carrier system that intestinal cells use to absorb Ca2+ from ingested food | essential regulator |
| insulin is synthesized as part of a larger polypeptide chain called | proinsulin |
| if excess glucose is available, after energy needs have been met, it is then | converted to fat |
| thyrotropin-releasing hormone (TRH), antidiuretic hormone (ADH), gonadotropin-releasing hormone (GnRH), oxytocin, & epinephrine are all hormones known to act on their target cells via | PIP2 mechanism |
| site of release & function of oxytocin | posterior pituitary; causes uterine contractions |
| when receptor activates G protein, hormone binding causes receptor to __ __, allowing it to bind a nearby inactive G protein | change shape |
| compared with other organs of the body the endocrine glands are | small & unimpressive |
| endocrine organs are not __ __ in the body | grouped together |
| targeting the bony matrix, calcitonin __ Ca2+ uptake & incorporation into bone matrix | stimulates |
| producing salty urine | natriuretic |
| cyclic AMP mechanism involves interaction of __ plasma membrane components to determine intracellular levels of cyclic AMP | three |
| all anterior pituitary hormones except for __ hormone affect their target cells via cyclic AMP second-messenger system | growth |
| most frequent abnormality of anterior pituitary tumors | hyperprolactinemia |
| influences body water balance | ADH |
| most anterior pituitary hormone release is regulated by releasing/inhibiting hormones by | the hypothalamus |
| after touching posterior lobe, anterior lobe of pituitary loses it connection with oral mucosa & adheres to | neurohypophysis |
| gland that would produce the hormone needed to restore homeostasis for end of 9 month pregnancy | posterior pituitary |
| nerve bundles that run through the infundibulum and connect the neurohypophysis and the hypothalamus | hypothalamic-hypophyseal tract |
| primary & secondary capillary plexuses & intervening hypophyseal portal veins make up the | hypophyseal portal system |
| hormones are molecular __ rather than informational molecules | triggers |
| formation of glucose, especially by the liver, from noncarbohydrate sources, such as amino acids | gluconeogenesis |
| GH promotes growth and __ actions | metabolic |
| function of antidiuretic hormone | causes kidneys to conserve water |
| PIP2-calcium signaling mechanism, __ __ takes on second-messenger role, either by directly altering activity of specific enzymes & channels or by binding to intracellular regulatory protein calmodulin | liberated Ca2+ |
| site of release & function of ADH | posterior pituitary; causes kidneys to conserve water |
| hormone-producing glands arise from | all three embryonic germ layers |
| hyperinsulinism __ __ hypoglycemia | results in |
| hormone that would help to restore the balance for homeostatic imbalance of elevated levels of blood sugar | insulin |
| function of growth hormone | stimulates embryonic cells (stem cells) to undergo mitosis |
| bones have moth-eaten appearance on x-rays & tend to fracture spontaneously | osteitis fibrosa cystica |
| body system that includes internal organs that secrete hormones | endocrine system |
| lymphoid organ and endocrine gland active in immune response; site of maturation of T lymphocytes | thymus |
| calcium deposits that form is soft tissues throughout body & severely impair vital organ functioning | metastatic calcification |
| marked by retention of fluid, headache & disorientation due to brain edema, weight gain & decreased solute concentration in blood | syndrome of inappropriate ADH secretion (SIADH) |
| if myxedema results from lack of iodine, enlargement & protrusion of thyroid gland | endemic/colloidal goiter |
| pituitary dwarfism is homeostatic imbalance resulting from | hyposecretion of growth hormone |
| congenital condition that includes mental retardation, short disproportional body size, and a thick tongue and neck is caused by | deficiency of thyroxin |
| condition that would be balanced by insulin | high levels of blood sugar |
| intracellular second messenger that mediates the effects of the first (extracellular) messenger (hormone or neurotransmitter); formed from ATP by a plasma membrane enzyme (adenylate cyclase) | cyclic AMP |
| hormone that would help to restore the balance for homeostatic imbalance of excessive levels of Na+ in extracellular fluids | aldosterone |
| functional insulin "clipping" takes places in secretory vesicles just before insulin is released | from the beta cells |
| circulating insulin lowers blood glucose levels by enhancing membrane __ of glucose into body cells, especially muscle & fat | transport |
| depress cartilage /bone formation; inhibit inflammation by decreasing release of inflammatory chemicals; depress immune system; promote changes in cardiovascular, neural & GI function | excessive levels of glucocorticoids |
| once initiated responses to hormone receptor sites tends to be much __ __ than those induced by nervous system | more prolonged |
| severe hypothyroidism in infants | cretinism |
| in PIP2-calcium signaling mechanism, __ __ releases Ca2+ from intracellular storage sites | inositol trisphosphate (IP3) |
| __ of a circulating hormone in blood at any time reflects it rate of release & speed at which it is inactivated & removed from body | concentration |
| produces symptoms of uncontrolled sympathetic nervous system activity | hypersecretion of catecholamines |
| important in regulating tissue growth & development, as well as critical for normal skeletal & nervous system development/maturation, & reproductive capabilities | TH |
| by turning on transcription of genes concerned with glucose oxidation, TH | has calorigenic effect |
| peptide hormones secreted by thymus; thought to be involved in normal development of T lymphocytes & immune response | thymulin, thymopoietins, & thymosins |
| transcription of new messenger RNA is a function of | steroid hormones |
| rising blood levels of thyroid hormones act on pituitary & hypothalamus to | inhibit TSH secretion |
| GHIH is produced in the gut where its release inhibits virtually all gastrointestinal & pancreatic __ | secretions |
| target cell activation by hormone-receptor interaction __ __ on blood levels of hormone, relative numbers of receptors for that hormone on target cell, & affinity of binding btwn response to various stimuli & changes within body | depends equally |
| aldosterone secretion is __ by decreasing blood volume & pressure, as well as rising levels of K+ | stimulated |
| organ that produces thyroxine | thyroid gland |
| excessive urine output | polyuria |
| protein hormone released by parathyroid glands; single most important hormone regulating blood calcium level | parathyroid hormone (PTH)/parathormone |
| rising levels of glucocorticoids feed back and __ secretion of CRH & ACTH release | block |
| diuretic drugs __ effects of ADH and cause water to be flushed from the body | antagonize |
| insulin-producing cells of pancreas | beta cells |
| ACTH release is elicited by hypothalamic | corticotropin-releasing hormone (CRH) |
| resistin, an insulin antagonist, is a hormone produced by | adipose tissue |
| drinking alcoholic beverages __ ADH secretion | inhibits |
| hormones act at receptors in the plasma membrane when they are | water-soluble hormones |
| function of insulin | facilitates glucose transport into cells |
| thyroid-stimulating hormone (TSH) is also called | thyrotopin |
| TSH levels are __ during the day | lower |
| when steroid & thyroid hormones are present receptor-chaperonin complexes __ allowing hormone-bound receptor to bind to DNA & influence transcription | dissociate |
| as a rule, energy need are met first, followed by __ __ | glycogen formation |
| sensory end organ that responds to changes in osmotic pressure; continually monitors solute concentration of blood | osmoreceptor |
| enzyme called phospholipase C splits plasma membrane phospholipid called PIP2 into diacylglycerol (DAG) and inositol trisphosphate (IP3) | PIP2-calcium signaling mechanism |
| function of gastrin | stimulates stomach to released hydrochloric acid |
| circulating insulin lowers blood glucose levels by __ conversion of amino acids or fats to glucose | inhibiting |
| for steroid & thyroid hormones, activated receptor-hormone complex makes way to nuclear chromatin and then binds to region of DNA; this interaction "turns on" a gene that prompts transcription of DNA to produce | messenger RNA (mRNA) |
| PTH deficiency; often follows parathyroid gland trauma or removal during thyroid surgery | hypoparathyroidism |
| at high blood concentrations ADH causes __ of the visceral blood vessels | vasoconstriction |
| zymogen-secreting cells of the pancreatic; produce enzyme-rich juice that is carried by ducts to small intestine during digestion | acinar cells |
| glucagon is a(n) __ hormone | hypoglycemic |
| function of epinephrine | increases cell reactions during sympathetic response |
| under __ __ the resulting increase in ACTH blood levels causes an outpouring of cortisol from adrenal cortex | acute stress |
| steroids are | synthesized from cholesterol |
| derived from iodinated thyroglobulin | thyroid hormone |
| promotes activation of vitamin D3 thereby increasing absorption of Ca2+ by intestinal mucosal cells | step 3 PTH |
| posterior pituitary plus infundibulum; portion of the pituitary gland derived from the brain | neurohypophysis |
| hormone synthesized in the hypothalamus and secreted by the posterior pituitary; stimulates contraction of the uterus during childbirth and the ejection of milk during nursing | oxytocin |
| hormone produced by the anterior pituitary that stimulates ovarian follicle production in females and sperm production in males | follicle-stimulating hormone (FSH) |
| is limited, ranging from 10 seconds to several hours | duration of hormone action |
| only gonadal & adrenocortical hormones are | steroids |
| thyroid hormone; secretion and function similar to those of thyroxine (T_4) | triiodothyronine (T3) |
| receptor for lipid-soluble steroid & thyroid hormones are __ cell | inside |
| in order to save glucose for the __, cortisol mobilizes fatty acids from adipose tissue & encourages their increased use for energy | brain |
| hormones function of kidneys is secretion of | erythropoietin & renin |
| amount of Na+ in body largely determines __ of extracellular fluid | volume |
| condition that increase body energy requirements, such pregnancy & exposure of infants to cold, stimulate hypothalamus to secrete __ __ which triggers TSH release allowing it to overcome negative feedback controls | thyrotropin-releasing horomone (TRH) |
| binding of hormones to cellular receptors initiates responses that typically occur after __ __ of seconds or even days | lag period |
| in renin-angiotensin mechanism, specialized cells of __ __ in kidneys become excited when blood pressure/volume declines, and thus release renin | juxtaglomerular apparatus |
| hormone released by the kidneys that is involved with raising blood pressure | renin |
| aldosterone accounts for __ __ 95% of the mineralocorticoids produced | more than |
| endocrine glands have __ vascular & lymphatic drainage that receives their hormones | rich |
| required for absorption of Ca2+ from food | vitamin D |
| substance that inhibits or prevent urine formation | antidiuretic |
| excess of glucose lost from body in urine | glycosuria |
| glucocorticoid secretion is regulated by | negative feedback |
| some hormones are rapidly degraded by __ in their target cells | enzymes |
| occurs in situation where more than 1 hormones produces same effects at target cell & their combined effects are amplified | synergism |
| area referred to as our biological clock; richly supplied with melatonin receptors | suprachiasmatic nucleus |
| hypothalamic-hypophyseal tract arises from __ in spraoptic & paraventricular nuclei of hypothalamus | neurons |
| effect of calcitonin is is to __ blood Ca2+ | lower |
| hypophyseal portal system is where the regulation of hormone __ takes place for the anterior pituitary | secretion |
| principle hormone produced by zona reticularis | androgens |
| enzymes that phosphorylate various proteins, many of which are other enzymes | protein kinase |
| iodide is oxidized to iodine | step 3 synthesis of TH by follicle cells |
| neurohypophysis secretes | ADH |
| heart produces | atrial natriuretic peptide |
| in recent years, anterior pituitary has been dethroned by the __, which is now known to control the activity of the anterior pituitary | hypothalamus |
| release of catecholamines from adrenal medulla reinforce or prolong | fight-or-flight response |
| function of aldosterone | increases Na+ reabsorption in the kidneys |
| erythropoietin is secreted by interstitial cells in | kidneys |
| childbirth & milk ejection result from | positive feedback mechanisms |
| thyroid gland secretes | calcitonin |
| protein molecules produced by mRNA include enzymes that promote metabolic activities induced by that particular hormone & in some cases promote synthesis of structural proteins or proteins to be transported from target cell | for steroid & thyroid hormones |
| acting directly GH __ rate of glucose uptake and metabolism | decreases |
| tropic adenohypophyseal hormone that regulates secretion of thyroid hormones | thyroid-stimulating hormone (TSH) |
| TH enters a target cell and | initiates transcription of mRNA for protein synthesis |
| influences activity of only certain tissue cells, referred to as its target cells | given hormone |
| insulin stimulates amino acid uptake & protein synthesis in | muscle tissue |
| inactive form of vitamin D, when modified cholesterol molecules in epidermal cells are exposed to UV radiation | cholecalciferol |
| function of thymosin | essential for normal immune response |
| potent vasoconstrictor activated by renin; also triggers release of aldosterone by glomerulosa cells | angiotensin II |
| adrenal catecholamines __ __ essential for life | are not |
| principle hormone produced by zona fasciculate | glucocorticoids |
| hormones of the thymus gland are essential in | formation of immune cells |
| osteitis fibrosa cystica is caused by | increase in parathyroid hormone |
| hormone secreted by pineal gland; secretion peaks at night and helps set sleep-wake cycles; also a powerful antioxidant | melatonin |
| stimulation of __ __, by GH, leads to long bone growth | epiphyseal plate |
| function of ADH | increases water reabsorption in kidney tubules |
| blood glucose levels rise, blood vessels constrict & heart beats faster, blood is diverted from nonessential organs to heart & skeletal muscles & preganglionic sympathetic nerve endings weaving through adrenal medulla signal for catecholamine release | when sympathetic nervous system is mobilized, in flight-or-flight |
| each region of adrenal gland produces | its own hormones |
| hormone produced by adrenal cortex | aldosterone |
| act on intracellular receptors, which directly activate genes | lipid-soluble hormones |
| excessively high blood iodine concentrations inhibit | TH release |
| GH is a(n) __ hormone | anabolic |
| glucocorticoid produced by the adrenal cortex; release is promoted by ACTH; rising levels feed back to act on both hypothalamus & anterior pituitary | cortisol (hydrocortisone) |
| when one hormone opposes action of another hormone | antagonism |
| hypocalcemia resulting from functional hypoparathyroidism __ excitability of neurons & accounts for classical symptoms of tetany | increases |
| when ketones accumulate in blood, the blood pH drops and ketones begin to spill into the urine | ketoacidosis |
| iodide is trapped by active transport by follicle cell, then moves into lumen by facilitated diffusion | step 2 synthesis of TH by follicle cells |
| adenohypophysis secretes | TSH |
| polyuria, polydipsia, & polyphagia are the three __ __ of diabetes mellitus | cardinal signs |
| hormonal stimulus typically __ __ of proteins or regulatory molecules (such as enzymes within cell) | stimulates synthesis |
| GHIH releases is triggered by __ of GH & IGFs | feedback |
| parathyroid glands are arranged in thick branching cords containing scattered __ cells and large numbers of smaller __ cells | oxyphil; chief |
| sympathetic nerve stimulation causes release of epinephrine and norepinephrine | from adrenal medulla |
| over two dozen steroid hormones synthesized by adrenal cortex are called | corticosteroids |
| disease caused by deficient insulin release or by insulin resistance, leading to inability of the body cells to use carbohydrates | diabetes mellitus (DM) |
| steroid hormones influence cellular activities by | binding to DNA and forming a gene-hormone complex |
| in cardiovascular organs aldosterone is a(n) | paracrine |
| chronic disease of adults marked by enlargement of the bones of the extremities, face, and jaw that is caused by overactivity of the pituitary gland secretion of GH | acromegaly |
| one molecule of glucagon can release 100 million molecules of __ into the blood | glucose |
| pulmonary cancers are known to | secrete ADH |
| down-regulation involves | loss of receptors & prevents target cells from overreacting to persistently high hormone levels |
| aterial blood is delivered to pituitary via __ branches of internal carotid arteries | hypophyseal |
| gonadotropins are virtually __ from blood of prepuberty boys & girls | absent |
| may compete for same receptors, act through different pathways, or even cause down-regulation of receptors for antagonistic hormone | antagonistic hormone |
| hormone-producing pyramid-shaped organs located superior to kidneys; each consists of medulla & cortex areas | adrenal glands |
| biologically active lipids are released by nearly all cell membranes; includes leukotrienes & prostaglandins | eicosanoids |
| CNS neurotransmitter involved in control of appetite | melanocyte-stimulating hormone (MSH) |
| one of major effects of atrial natriuretic peptide (ANP) is to | inhibit renin-angiotensin mechanism |
| hormone produced by posterior pituitary | antidiuretic hormone |
| attachment of 1 iodine to a tyrosine produces | monoiodotyrosine (MIT or T1) |
| neuroendocrine gland located beneath the brain that serves a variety of functions including regulation of gonads, thyroid, adrenal cortex, lactation, and water balance | pituitary gland |
| hypersecretion of gonadocorticoids causes | adrenogenital syndrome |
| thyroid gland has ability to store its hormone extracellulary & stored amount remains constant & sufficient to provide levels of hormone release for | two to three months |
| signal that would affect local cells by releasing chemicals into extracellular fluid | paracrine |
| stimulation of skeletal muscles by GH promotes increased __ __ | muscle mass |
| to secrete | -crine |
| hypersecretion of aldosterone; typically results from adrenal tumors | aldosteronism |
| steroid hormones are not __ in cells | stored |
| controls activity of anterior pituitary | hypothalamus |
| function of calcitonin | lowers blood Ca2+ levels |
| hormones are __ __ signals that travel in blood or lymph throughout the body | "long-distance" chemical |
| internal & external factors that alter normal ACTH rhythm by triggering CRH release include | fever, hypoglycemia, & stressors of all types |
| androstenedione & dehydroepiandrosterone (DHEA) are converted to __ in tissue cells in females | estrogens |
| hormone produced by the hypothalamus and released by the posterior pituitary; stimulates the kidneys to reabsorb more water, reducing urine volume | antidiuretic hormone (ADH) |
| hormone released by fat cells that signals satiety; serves to tell body how much stored energy is available | leptin |
| thymus produces | thymosin |
| originates from a superior outpocketing of oral mucosa (Rathke's pouch) and is formed from epithelial tissue | anterior lobe of pituitary |
| is either amino acid-based hormones or steroids | chemical classification of hormones |
| hormones may communicate with their target cells __ __ to an extracellular receptor | by binding |
| coupled to Na+ is regulation of other ions, including | K+, H+, HCO3 (bicarbonate), & Cl- (chloride) |
| ovaries produce important hormones of | estrogen & progesterone |
| Na+ & K+ __ are crucial to overall body homeostasis | regulation |
| tiny cell clusters (scattered among acinar cells)that produce pancreatic hormones | pancreatic islets |
| hormones released by adipose cells that affect sensitivity of cells to insulin | resistin & adiponectin |
| humoral stimuli, falling glucose levels, prompt __ cells to secrete glucagon | alpha |
| disease characterized by passage of a large quantity of dilute urine plus intense thirst and dehydration caused by inadequate release of antidiuretic hormone (ADH) | diabetes insipidus |
| fall in amino acid concentration in blood as liver cells sequester glucagon molecules to make new glucose molecules | secondary effect of glucagon |
| pancreatic beta cells are stimulated to secrete insulin by rising __ __ of amino & fatty acids | plasma levels |
| some __ __ cells also produce peptides, such as somatostatin, pancreatic polypeptide (PP), etc. | pancreatic islet |
| during puberty to gondotrophs of anterior pituitary are activated and gonadotropin levels begin to rise, causing | gonads to mature |
| release of thyroid-stimulating hormone (TSH) follows | hypothalmic-pituitary-target endocrine feedback loop |
| ADH prevents wide swings in __ balance | water |
| include swollen "moon" face, redistribution of fat to the abdomen & posterior neck, tendency to bruise, & poor wound healing | cushingoid signs |
| receptor for water-soluble hormones must be in __ __ since these hormones cannot enter cell | plasma membrane |
| because of amplification effect of cAMP mechanisms, most hormones need to be present __ __ to cause desired results | only briefly |
| permissive effect for normal timely development of reproductive structures (along with reproductive hormones) | thyroid hormone |
| autoimmune response is said to be cause for __ __ diabetes | type I |
| prolactin-releasing factor | TRH |
| more potent catecholamine stimulator of metabolic activities, bronchial dilation, & increased blood flow to skeletal muscles & heart | epinephrine |
| extended deficiency of dietary magnesium, required for PTH secretion) can cause | functional hypoparathyroidism |
| hyperinsulinism can result from an __ of insulin | overdose |
| long polymers of amino acids | proteins |
| in females, LH independently promotes synthesis & release of __ hormones | ovarian |
| cell clusters forming superficial layer; produce mineralocorticoids | zona glomerulosa |
| adrenal medulla synthesize catecholamines via __ __ from tyrosine to dopamine to NE to epinephrine | molecular sequence |
| major hormone secreted by thyroid follicles; stimulates enzymes concerned with glucose oxidation | thyroid hormone (TH) |
| all adrenal hormones help up | cope with stressful situations |
| insulin also influences | protein & fat metabolism |
| homeostatic imbalance of gigantism would be due to the hormone deficiency/overproduction of | overproduction of GH |
| "hormone response element" is located on the | cell DNA |
| attachment of 2 iodine to a tyrosine produces | diiodotyrosine (DIT or T2) |
| all of effects of renin-angiotensin mechanism are ultimately involved in | raising blood pressure |
| many anterior pituitary hormones stimulate other endocrine to | release their hormones |
| androstenedione & dehydroepiandrosterone (DHEA) are converted to __ in tissue cells in males | testosterone |
| condition that would be balanced by thyroxine | decrease in body metabolism |
| responds to hormone binding by prompting cell to perform, or turn on, some gene-determined preprogrammed function | hormone receptor |
| follicle-stimulating hormone | stimulates gamete (sperm or egg) production |
| hormone that regulates the secretory action of another endocrine organ | tropic hormone |
| organ that produces ADH | posterior pituitary (neurohypophysis) |
| all hypothalamic regulatory hormones are __ __ based | amino acid |
| most peripheral tissues have enzymes needed to convert T4 to T3 by | removing one iodine |
| disorder resulting from hyperactive thyroid gland | Grave's disease |
| declining blood Ca2+ levels inhibit C cell __ Activity | secretory |
| when TSH from anterior pituitary binds to receptors on thyroid follicle cells, second response is to | begin synthesizing more colloid to restock thyroid follicle lumen |
| chemicals that exert their effects on same cells that secrete them | autocrines |
| group of active metabolites of cholecalciferol (vitamin D3);increases intestinal absorption of calcium & phosphate, enhances bone resorption, & prevents rickets | dihydroxycholecalciferol/calcitriol |
| Ca2+ homeostasis is essential for so many functions, including | transmission of nerve impulses, muscle contraction, & blood clotting |
| water-soluble hormones are coupled via regulatory molecules called __ to one/more intracellular 2nd messengers which mediate target cell's response | G proteins |
| under normal circumstances glucocorticoids help body to adapt to intermittent food intake by keeping __ __ levels fairly constant, and maintain blood pressure by increasing action of __ | blood glucose; vasoconstrictors |
| pancreas, gonads, & placenta, along with performing other functions, | contain endocrine tissue |
| growth hormone stimulates | most body cells to increase in size and divide |
| pineal gland secretes | melatonin |
| hyperinsulinism can result from __ __ tumor | islet cell |
| GH encourages use of __ for fuel, thus conserving glucose | fats |
| pineal gland produces | melatonin |
| iodine is required for | synthesis of thyroid hormone |
| most hormones are __ __ based | amino acid |
| gland that would produce the hormone needed to restore homeostasis for delayed/stunted growth | anterior pituitary |
| hormone produced by anterior pituitary | growth hormone |
| as blood levels of __ __, the expulsive contractions of labor gain momentum and finally end in birth | oxytocin rise |
| adrenal glands are enclosed in | fibrous capsule & cushion of fat |
| function of thyroxine | increases the metabolic rate |
| gland that would produce the hormone needed to restore homeostasis for loss of Na+ from profuse sweating | adrenal cortex |
| in liver, binding of glucagon activates enzymes that breakdown glycogen, releasing | glucose to blood |
| made largely of axons of hypothalamic neurons; stores antidiuretic hormone (ADH) and oxytocin | posterior pituitary |
| cyclic AMP is used by __ & __ receptors | neurotransmitters; olfactory |
| most hormones are removed from the blood by | kidneys or liver |
| TSH | stimulate thyroid gland |
| TSH levels __ just before sleep | peak |
| hormone such as testosterone that controls male secondary sex characteristics | androgen |
| cords & branching networks are a situation that __ contact between endocrine glands & capillaries surrounding them | maximizes |
| primary capillary plexus is located in | the infundibulum |
| feedback inhibition & others are __ factors that affect endocrine system | turn-off |
| coupling of MIT & DIT produces | T3 |
| steroid hormones that affect glycogenesis in the liver; anti-inflammatory, are active in protection against stress, and affect carbohydrate and protein metabolism | glucocorticoids |
| includes pituitary, thyroid, parathyroid, adrenal, & pineal glands | endocrine glands |
| somatostatin is considered paracrine because it acts on | cells other than those that secrete it |
| hormones bring about their characteristic effects on target cells by __ cell activity, either decreasing/increasing rates of normal cellular processes | altering |
| initiate series of protein phosphorylations that triggers specific cell responses | relay proteins |
| thyroid hormone (TH) is often referred to as the body's | major metabolic hormone |
| function of prolactin | stimulates mild production |
| oxytocin acts via __ second-messenger system to mobilize Ca2+ allowing stronger contractions | PIP-Ca2+ |
| cortisol's __ __ effects is to provoke gluconeogenesis | prime metabolic |
| down-regulation involves loss of receptors & prevents target cells from overreacting to | persistently high hormone levels |
| water-soluble hormones exhibit | shortest half-life |
| site of release & function of LH | anterior pituitary; causes ovulation & interstitial cells to produce testosterone in testes |
| after glucose enters target cell, insulin binding triggers enzymatic activities that convert glucose to | fat, particularly in adipose tissue |
| in PIP2-calcium signaling mechanism, intracellular calcium ions act as | final mediator |
| prompts kidneys to increase their production of salty urine & inhibits aldosterone release by adrenal cortex; thereby decreasing amount of sodium in extracellular fluid, reducing blood volume & pressure | ANP |
| insulin & other growth factors work __ second messengers | without |
| function of androgens | produce masculinizing effects when produced in large quantities |
| cells forming middle layer; arranged in more/less linear cords; produce glucocorticoids | zona fasciculata |
| category of hormone of aldosterone | mineralocorticoids |
| each activated adenylate cyclase generates large numbers of cAMP molecules, and a single kinase enzyme can catalyze | hundreds of reactions |
| catecholamine neurotransmitter and adrenal medullary hormone, associated with sympathetic nervous system activation | norepinephrine (NE) |
| large molecule isolated from anterior pituitary; prohormone & source of andrenocorticotropic hormone, enkephalin & beta endorphin, & melanocyte-stimulating hormone (MSH) | pro-opiomelanocortin (POMC) |
| hormone that would help to restore the balance for homeostatic imbalance of too much Ca2+ in blood | calcitonin |
| in females, LH independently triggers __ | ovulation |
| because TH provokes an increase in number of __ __ in blood vessels, it plays an important role in maintaining blood pressure | adrenergic receptors |
| gland/organ that produces calcitonin | thyroid gland |
| hormone produced by the adrenal cortex that regulates Na+ reabsorption and K+ secretion by the kidneys | aldosterone |
| hormone secreting cells sprinkled in mucosa of GI tract; release several peptide hormones that help regular wide variety of digestive functions | enteroendocrine cells |
| for steroid & thyroid hormones, once mRNA produced, it is then translated on __ __, producing specific protein molecules | cytoplasmic ribosomes |
| stimulus for producing insulin is | high blood glucose concentration |
| length of time for a hormone's blood level to decrease by half; varies from fraction of minute to a week | half-life |
| enhances sensitivity to insulin & is secreted by adipose tissue | adiponectin |
| insulin is the major __ __ that counterbalances the many hypoglycemic hormones | hypoglycemic factor |
| under cortisol's influence, __ __ are broken down to provide building blocks for repair or for making enzymes to be used in metabolic processes | stored proteins |
| acidophilic cells found in the parathyroid glands | oxyphil cells |
| preganglionic fibers of sympathetic neurons stimulate adrenal medulla to | produce epinephrine & norepinephrine |
| hormone that skin produces | cholecalciferol |
| pathology of glucocorticoid excess; may be caused by ACTH-releasing pituitary tumor, ACTH-releasing malignancy of lungs, pancreas, or kidneys, or tumor of adrenal cortex | Cushing's disease |
| synthesize hormones identical to those made in normal endocrine glands in excess/uncontrolled fashion leading to problems due to hormone-mediated pathology | certain tumor cells, such as lung/pancreatic cancer |
| secretion of digestive enzymes is a(n) __ function for the pancreas | exocrine |
| during cAMP mechanism, activated G protein (moving along membrane) binds to effector enzyme | adenylate cyclase |
| pineal gland indirectly receives input from __ pathways concerning the intensity & duration of daylight | visual |
| condition that would be balanced by aldosterone | loss of Na+ from extracellular fluids |
| leptin binds to CNS neurons concerned with __ __ | appetite control |
| influences both blood volume & pressure by regulating release of aldosterone and therefore Na+ & water reabsorption by kidneys | renin-angiotensin mechanism |
| most of hormone-producing cells in endocrine glands are arranged in __ & __ networks | cords; branching |
| hormone from hypothalamus that inhibits GH release | growth hormone-inhibiting hormone (GHIH) |
| during cAMP mechanism, G protein cleaves terminal phosphate group off GTP in much same way that ATPase enzymes | hydrolyze ATP |
| in males, LH stimulates __ __ of testes to produce testosterone | interstitial cells |
| include estrogens & progesterone, as well as human chorionic gonadotropin (hCG) | placental hormones |
| lumen of thyroid follicle __ colloid | stores |
| gland that would produce the hormone needed to restore homeostasis for high blood sugar due to eating too many sweets | pancreas |
| organ that produces glucagon | pancreas |
| function of parathyroid hormone | raises blood Ca2+ levels |
| type of intracellular enzymatic cascade during cAMP has a huge __ effect | amplification |
| inhibiting effects of insulin counter any metabolic activity that would increase __ __ of glucose | plasma levels |
| as cAMP mechanism reaction cascades through 1 enzyme intermediate after another, number of product molecules __ __ at each step | increases dramatically |
| neural control mechanism | axons cause hormone release |
| somatostatin & sympathetic nervous system activation __ insulin release | depress |
| hormone produced by pancreas | insulin |
| in the body the __ system makes certain adjustment to maintain homeostasis by overriding normal endocrine controls | nervous |
| increases basal metabolic rate & body heat production | calorigenic effect |
| __ __ __ can be interrupted by acute stress of any variety as higher CNS center override the usually inhibitory effects of elevated cortisol level & trigger CRH release | normal cortisol rhythm |
| endocrine system orchestrates processes that go on for | relatively long periods or even continuously |
| chief hormone produced by the adrenal medulla; also called adrenaline | epinephrine |
| is that glucose handling is improved & body fat is reduced | result of osteocalcin |
| hormones secreted by neurons; released by posterior pituitary | neurohormones |
| organ that produces renin | kidneys |
| in PIP2-calcium signaling mechanism, once Ca2+ binds to calmodulin it activates enzymes that __ cellular response | amplify |
| sex hormones, primarily androgens, secreted by the adrenal cortex | gonadocorticoids |
| IGFs stimulate actions required for growth through formation of __ & deposition of __ __ | collagen; bone matrix |
| cAMP, which is free to diffuse throughout cell, triggers __ of chemical reactions by activating protein kinase | cascade |
| only connection between anterior lobe of pituitary & hypothalamus is | vascular |
| glucagon & epinephrine cause liver to release glucose to blood; when they act together amount of glucose released is about 150% of what is released when each hormone | acts alone |
| major types of stimuli trigger endocrine glands to manufacture & released their hormones | humoral, neural, & hormonal |
| hormone that stomach produces | gastrin |
| severe stress due to hemorrhage, infection, or physical/emotional trauma evokes a dramatically __ output of glucocorticoids, which help body negotiate crisis | higher |
| ANP blocks renin & aldosterone secretion & inhibits other __ mechanisms that enhance water & Na+ reabsorption | angiotensin-induced |
| vitamin D ingested or produced by skin is a(n) | inactive form |
| prolactin release is controlled primarily by inhibitory hormone prolactin-inhibiting hormone (PIH), known as | dopamine |
| primary function of kidney cells is | excretion of body waste |
| nerve fibers stimulate hormone release | neural stimuli |
| hormone that would help to restore the balance for homeostatic imbalance of decreased levels of blood sugar | glucagon |
| TSH levels remain __ during the night | high |
| tyrosine kinase enzyme that is activated by autophosphorylation when insulin binds | insulin receptor |
| under severe stress, hypothalamus secretes more corticotropin-releasing hormone (CRH), 7 resulting rise in ACTH blood levels steps up rate of aldosterone secretion to small extent; resulting in increased blood volume/pressure | ACTH mechanism to regulate aldosterone secretion |
| luteinizing hormone (LH) & follicle-stimulating hormone (FSH), produced by anterior pituitary, are referred to collectively as | gonadotropins |
| pain, low blood pressure, & drugs such as nicotine, morphine, & barbiturates are all stimuli that trigger | ADH release |
| adenohypophyseal hormone that stimulates the breasts to produce milk; protein hormone structurally similar to GH | prolactin (PRL) |
| hormone produced by adrenal medulla | epinephrine |
| placenta produces | human chorionic gonadotropin (HCG) |
| condition that would be balanced by ADH | loss of body fluids |
| driven by patterns of eating & activity, occur in a definite pattern throughout day & night | cortisol secretory bursts |
| in renin-angiotensin mechanism, when renin is released it cleaves off part of plasma protein angiotensinogen, which triggers | enzymatic cascade leading to formation of angiotensin II |
| within | endo- |
| endocrine organs are __ __ throughout the body | widely scattered |
| function of growth hormone | causes cells to undergo mitosis & increase in size |
| releasing & inhibiting hormones secreted by neurons in ventral hypothalamus circulate to __ __ via the hypophyseal portal system | anterior pituitary |
| aldosterone is also secreted by __ organs | cardiovascular |
| function of oxytocin | stimulates milk ejection from mammary glands |
| short chains of amino acids | peptides |
| endocrine glands released their hormones into | surrounding tissue fluid |
| thyroid-stimulating hormone, andrenocorticotropic hormone, follicle-stimulating hormone, & luteinizing hormone are all | tropic |
| hormone-secreting part of diencephalon of brain thought to be involved in setting biological clock & influencing reproductive function | pineal gland |
| stress results in __ __ in blood levels of glucose, fatty acids, and amino acids | dramatic rise |
| breakdown of glycogen to glucose | glycogenolysis |
| glycogenolysis, gluconeogenesis, release of glucose to blood by liver cells, causing blood glucose levels to rise | major targets of glucagon |
| posterior lobe of pituitary is actually part of | the brain |
| 2 innermost layers of adrenal cortex __ __ of glucocorticoids & gonadocorticoids, although each layer predominately produces one type | share production |
| small endocrine glands located on the posterior aspect of the thyroid gland | parathyroid glands |
| function of glucocorticoids | increase blood levels of glucose, fatty acids, and amino acids during stress |
| considered a neuroendocrine organ because, along with its neural functions, it produces & releases hormones | hypothalamus |
| a given hormone influences __ __ __ referred to as "target cells" | only certain cells |
| Addison's disease is homeostatic imbalance that usually results from | deficits in both glucocorticoids & mineralocorticoids |
| main effect of insulin is to | lower blood sugar |
| iodinated tyrosines are linked together to form T3 & T4; enzymes in colloid link MIT & DIT together; hormones are still part of thyroglobulin colloid | step 5 synthesis of TH by follicle cells |
| synthesis & release, or blood levels, of most hormones are regulated by a(n) __ __ | negative-feedback system |
| thyroxine-binding globulins (TBGs) are produced by | the liver |
| lipid-soluble hormones travel in bloodstream attached to | plasma proteins |
| "hormone response element" represents | site for a hormone to bind |
| acting directly GH mobilizes fat for depots for transport to cells, thus increasing levels of | fatty acids |
| thymic hormones are involved in __ | immunity |
| aldosterone's regulatory effects are __ lasting approx. 20 minutes, allowing plasma electrolyte balance to be precisely controlled | brief |
| function of gonadotropins | regulate functions of gonads in both sexes |
| function of follicle-stimulating hormone | affects functions of ovaries & testes |
| composed largely of pituicytes and nerve fibers | posterior pituitary |
| function of HCG | helps to sustain pregnancy |
| NOT a true hormone, but, rather, a trophic substance | TSH |
| endocrine glands derived from __ produce steroid hormones | mesoderm |
| scientific study of hormones & endocrine organs | endocrinology |
| single most abundant cation in extracellular fluid is | Na+ |
| condition that would be balanced by parathyroid hormone | decrease in blood Ca+ levels |
| hydrolytic breakdown of proteins into simpler, soluble substances such as peptides and amino acids, as occurs during digestion | proteolysis |
| calcitonin is given therapeutically to patient's with | Paget's disease |
| PIP2-calcium signaling mechanism is mechanisms of hormone action in which | intracellular calcium ions act as a final mediator |
| major target(s) of GH are | bones & skeletal muscles |
| during cAMP mechanism, for as long as activated Gs is bound to it, adenylate cyclase generates second messenger cAMP from | ATP |
| skeleton contains considerable amount of __ __ in its matrix, making it an apt target organ of PTH | calcium salts |
| function of cholecalciferol | activated by the kidneys to Vitamin D; stimulates active absorption of Ca2+ by intestinal cells |
| GH deficiency in children results in slowed long bone growth | pituitary dwarfism |
| central cavity of thyroid follicle | lumen |
| site of release & function of FSH | anterior pituitary; causes ovarian follicles to grow & produce estrogen & spermatogenesis in testes |
| symptoms include hyperglycemia, increased metabolic rate, rapid heartbeat & palpitations, hypertension, intense nervousness & sweating; tumor of chromaffin cells of adrenal medulla | pheochromocytoma |
| cortisol enhances the __ nervous system's vasoconstrictive effects, and the rise in blood pressure & circulatory efficiency that results helps ensure that these nutrients are quickly distributed to cells | sympathetic |
| normal endocrine controls can be __ __ by the nervous system | directly overridden |
| anterior pituitary has traditionally been called the "master endocrine gland" because | many of the numerous hormones it produces regulate the activity of other endocrine glands |
| secretion of parathyroid hormone is a good example of | humoral stimuli |
| adrenal glands are often referred to as | suprarenal glands |
| principle hormone produced by zona glomerulosa | mineralocorticoids |
| steroidal or amino acid–based molecules released to the blood that act as chemical messengers to regulate specific body functions | hormones |
| function of thyroxine | increase metabolic rate |
| receptor-chaperonin complexes that takes place in absence of steroid & thyroid hormones, keep receptors from binding to DNA and may | protect them from proteolysis |
| hormone that stimulates growth in general; produced in the anterior pituitary; also called somatotropin (STH) | growth hormone (GH) |
| endocrine glands are also called | ductless glands |
| protein kinases affect enzymes by | adding phosphate group (phosphorylation) to enzyme |
| adrenal medulla is a(n) __ stimulated gland | neurally |
| polypeptide hormone released by the thyroid; lowers blood calcium levels only when present at high (therapeutic) levels | calcitonin |
| G protein activate adenylate cyclase | 3rd step of cAMP mechanism |
| insulin's effects are most obvious when we have | just eaten |
| action of cAMP persists only briefly because molecules is rapidly degraded by intracellular | enzyme phosphodiesterase |
| main effect of insulin is to __ blood glucose levels, but it also influences protein & fat metabolism | lower |
| hormones released in response to humoral stimuli include | PTH, insulin, & aldosterone |
| endocrine glands secrete their hormones in direct response to changing blood levels of certain critical ions & nutrients | humoral stimuli |
| endocrine function of adipose cells release | leptin |
| fluctuating blood levels of K+ directly influence zona glomerulosa cells in adrenal cortex; increased K+ stimulates aldosterone release, whereas decreased K+ inhibits it | plasma concentration of K+to regulate aldosterone secretion mechanism |
| chromaffin cells are modified ganglionic __ __ that synthesize catecholamines | sympathetic neurons |
| hormone that adipose tissue produces | leptin |
| there is no __ __ connection between anterior lobe of pituitary & hypothalamus | direct neural |
| inner portion; more like a knot of nervous tissue; part of sympathetic nervous system | adrenal medulla |
| gland/organ that produces epinephrine | adrenal medulla |
| falling TH blood levels trigger __ of TSH | release |
| hormones are long-distance chemical signals that travel in __ throughout the body | blood/lymph |
| situation when 1 hormone cannot exert its full effects without another hormone being present | permissiveness |
| gland/organ that produces adrenocorticotropic hormones | pituitary gland |
| any of a class of enzymes that catalyze the cleaving of phosphodiester bonds, such as those between nucleotides in nucleic acids, to produce smaller nucleotide units | phosphodiesterase |
| gland/organ that produces parathyroid hormone | parathyroid glands |
| ADH is also called | vasopressin |
| insulin antagonist secreted by adipose tissue | resistin |
| cholecalciferol is hormone secreted from | skin |
| water-soluble hormones are all amino acid-based hormones except for | thyroid hormone |
| in females, LH works with FSH to cause an __ __ __ to mature | egg-containing ovarian follicle |
| function of atrial natriuretic peptide | reduces blood volume, blood pressure, and blood sodium concentration by signaling the kidneys |
| category of hormone of androgens | gonadocorticoids |
| hormonal, humoral, & neural stimuli are __ factors that affect endocrine system | turn-on |
| most T3 is formed at the target tissue by | conversion of T4 to T3 |
| hormone from hypothalamus that stimulates GH release | growth hormone-releasing hormone (GHRH) |
| ADH | stimulates kidney tubules to reabsorb water from urine |
| because effects of eicosanoids are typically highly localized, they generally act as paracrines/autocrines instead of | true hormones |
| TH provokes increase in number of __ receptors in blood vessels, playing important role in maintaining blood pressure | adrenergic |
| involves synthesis & activation of proteins required for Na+ transport, such as Na+-K+ ATPase, pump that exchanges Na+ for K+ | mechanism of aldosterone activity |
| if left untreated hypoparathyroidism can | lead to paralysis/death |
| GHIH, dopamine, & rising levels of glucocorticoids are factors that | inhibit TSH release |
| true hormones influence __ targets | distant |
| function of mineralocorticoids | regulate Na+ reabsorption by the kidneys and thereby regulates other electrolyte levels |
| for vitamin D to exert its physiological effects it must be converted by kidneys to its active vitamin D3 form of | calcitriol |
| population of cells in thyroid gland that produce calcitonin; lie in follicular epithelium but protrude into soft connective tissue that separates & surrounds thyroid follicles | parafollicular cells |
| Cushing's disease is most often a result of clinical administration of __ __ of glucocorticoid drugs | pharmacological doses |
| cholecalciferol is modified in the __ and becomes fully activated in the __ | liver; kidneys |
| adrenal gland secretes | aldosterone |
| osteocalcin levels are __ in type 2 diabetes | low |
| iodine is attached to tyrosine at junction of follicle cell apex & colloid, & is mediated by peroxidase enzymes | step 4 synthesis of TH by follicle cells |
| hormonal control mechanism | hormone release is dependent upon other hormone levels |
| glucagon release is __ by rising blood glucose levels, insulin, & somatostatin | suppressed |
| __ __ for oxytocin are the smooth muscle cells of the uterus and the myoepithelial cells of the mammary glands | target tissues |
| adenylate cyclase converts ATP to cyclic AMP | 4th step of cAMP mechanism |
| catecholamine that has greater influence on peripheral vasoconstriction & blood pressure | norepinephrine |
| all anterior pituitary hormones are | proteins |
| hypophyseal portal system transports releasing & inhibiting hormones from hypothalamus to | anterior pituitary gland (adenohypophysis) |
| hormone bind receptor on plasma membrane | 1st step of cAMP mechanism |
| since some G proteins inhibit rather that activate adenylate cyclase, reducing cytoplasmic concentration of cAMP, even slight changes in levels of __ __ can influence target cell's activity | antagonistic hormones |
| FSH | stimulates development of the follicle in the ovaries |
| for the pancreas, production of insulin and glucagon is a(n) __ function | endocrine |
| fatty acid metabolites; strong organic acids | ketones |
| gland that would produce the hormone needed to restore homeostasis for drop in blood levels of Ca2+ due to extreme inactivity | parathyroid |
| function of TSH | stimulates the thyroid gland to produce thyroxine |
| certain prostaglandins released by smooth muscle cells cause those smooth muscle cells to contract making it a(n) | autocrine |
| is high at night and low during daylight hours | blood level of melatonin |
| function of leptin | binds to CNS neurons concerned with appetite control |
| median tissue mass of thyroid gland | isthmus |
| produce the hormones renin and erythropoietin | kidney cells |
| prolonged exposure to high hormone concentration desensitizes target cells, sot that they respond less vigorously to hormonal stimulation | down-regulation |
| deficiency of hormones of adrenal medulla is not a problem because these hormones merely __ activities set into motion by sympathetic nervous system | intensify |
| local hormones are released into the __ __ and affect only adjacent cells in the same tissue | extracellular fluid |
| GHIH __ release of thyroid-stimulating hormone | blocks |
| cyclic AMP | cAMP |
| skin, the heart, and the kidneys contain cells or tissues that | produce hormones |
| when receptor activates G protein, it is activates as __ bound to it is displaced by high-energy compound __ | GDP (guanosine diphosphate); GTP (guanosine triphosphate) |
| hormone that kidney produces | erythropoietin |
| untreated symptoms of functional hypoparathyroidism progress to | respiratory paralysis & death |
| one of the largest of the body's endocrine glands; straddles the anterior trachea | thyroid gland |
| for a given level of hormone in the blood, a smaller number of __ receptors results in reduced target cell response or outright endocrine dysfunction | low-affinity |
| antagonism has a(n) __ affect | opposite |
| homeostatic imbalance of sympathetic nervous system overactivity would be due to the hormone deficiency/overproduction of | oversecretion of catecholamines |
| middle portion of proinsulin polypeptide chain is excised by enzymes releasing __ insulin | functional |
| most hormone breakdown products are excreted from body in | urine or feces |
| primary target of aldosterone is __ parts of kidney tubules, where it stimulate Na+ reabsorption & water retention accompanied by K+ elimination | distal |
| hormone formed by alpha cells of pancreatic islets; raises the glucose level of blood; 29-amino-acid polypeptide | glucagon |
| PTH release stimulates osteoclast to digest some of the bony matrix and release ionic calcium & phosphates to the blood | step 1 PTH |
| G protein that stimulates adenylate cyclase | Gs |
| PTH increases Ca2+ levels in blood by stimulating targets organs of | skeleton, kidneys, & intestine |
| large, lipid-laden cortical cells of adrenal cortex are arranged in | 3 layers/zones |
| hormonal stimulus typically stimulates | mitosis |
| endocrine function of thymus is release | thymic hormones |
| at cellular level insulin activates its receptor __ __ enzyme which phosphorylates specific proteins beginning the cascade that leads to increased glucose uptake & insulin's other effects | tyrosine kinase |
| hypothalamus is considered a __ organ | neuroendocrine |
| synthesis & release of most hormones are regulated by | negative feedback system |
| function of melatonin | associated with drowsiness at night |
| hormonal stimuli promote rhythmic hormone release, with hormone blood levels rising & falling in a specific pattern | hypothalamic-pituitary-target endocrine organ feedback loop |
| function of testosterone | associated with sexual maturity in males; needed for normal sperm production |
| humoral control mechanisms | monitoring blood levels of substances and correct them |
| insulin roles in the __ participate in neuronal development, feeding behavior, & learning/memory | brain |
| principle hormone produced by beta cells | insulin |
| IGFs produced in tissues other than liver act as | paracrines |
| outer portion; encapsulating medulla & forming bulk of gland; glandular tissue derived from embryonic mesoderm | adrenal cortex |
| __ __ of most body tissues is controlled directly by TH | metabolic rate |
| signaling chemicals that mediate inflammation & some allergic reactions | leukotrienes |
| released by one population of pancreatic cells inhibits release of insulin by a different population of pancreatic cells making it a(n) | paracrine |
| progesterone induces loss of estrogen receptors in uterus, this __ estrogen's actions; while estrogen causes same cells to produce more progesterone receptors, __ ability to respond to progesterone | antagonizing; enhances |
| characterized by persistent elevated blood glucose levels, dramatic losses in muscle/bone protein, & water/salt retention leading to hypertension & edema | Cushing's syndrome |
| family of growth-promoting proteins produced by liver, skeletal muscles, bone, & other tissues; mediated growth promoting effects of GH | insulin-like growth factors (IGFs) |
| function of glucagon | increases blood sugar level by stimulating liver |
| in the liver GH encourages glycogen breakdown & | release of glucose to blood |
| most abundant parenchymal cells of the parathyroid, being polygonal epithelial cells rich in glycogen, having granular cytoplasm and vesicular nuclei, and arranged in plates or cords | chief cells |
| hormone secreted by osteoblasts that prods pancreatic beta cells to divide & secrete more insulin; restricts fat storage by adipocytes & triggers release of adiponectin | osteocalcin |
| ADH targets __ __ via cAMP | kidney tubules |
| function of cholecystokinin | stimulates release of bile |
| located in the infundibulum, it communicates inferiorly via the small hypophyseal portal veins with a secondary capillary plexus | primary capillary plexus |
| anterior pituitary; the glandular part of the pituitary gland | adenohypophysis |
| intracellular molecule generated by the binding of a chemical (hormone or neurotransmitter) to a plasma membrane receptor; mediates intracellular responses to the chemical messenge | second messengers |
| homeostatic imbalance of diabetes insipidus would be due to the hormone deficiency/overproduction of | hyposecretion of ADH |
| thyroid hormone receptors are __ bound to DNA even in absence of thyroid hormone | always |
| hypercalcemia causes __ of nervous system and formation of __ stones | depression; kidney |
| endocrinology involves the study of | endocrine organs and hormones |
| in both sexes LH promotes production of __ hormones | gonadal |
| function of erythropoietin | stimulates the production of red blood cells |
| is NOT a major endocrine organ, but produces hormones in addition to its major function | kidneys |
| function of adrenocorticotropic hormone | causes adrenal cortex to produce hormones |
| site of release & function of TSH | anterior pituitary; causes thyroid gland to synthesize thyroxine |
| in PIP2-calcium signaling mechanism, ___ activates protein kinase C which triggers responses within target cell | diacylglycerol (DAG) |
| hormones circulate through the blood as | free or bound to protein carrier |
| for a given level of hormone in the blood, a large number of __ receptors produce a pronounced hormonal effect | high-affinity |
| is principal hormone stimulating cellular metabolism, and nearly all body cells have its receptors | thyroxine |
| major hyposecretory disorder of adrenal cortex, usually involves deficits in both glucocorticoids & mineralcorticoids; weight loss, plasma glucose & sodium levels drop, & potassium levels rise | Addison's disease |
| most T3 is generated in | peripheral tissues |
| endocrine system influences __ activity by means of hormones | metabolic |
| when one hormone opposes the action of another hormone, the interaction is called | antagonism |
| hormone that would help to restore the balance for homeostatic imbalance of lowered levels of Ca2+ in the blood | parathyroid hormone |
| aldosterone __ Na+ reabsorption from perspiration, saliva, & gastric juice | enhances |
| phenomenon in which target cells form more receptors in response to rising blood levels of specific hormone to which they respond | up-regulation |
| insulin does no accelerate glucose entry into liver, kidney, & brain tissues because | they have easy access to blood glucose regardless of insulin levels |
| lysosomal enzymes cleave T4 & T3 from thyroglobulin & hormones diffuse from follicle cell into bloodstream | step 7 synthesis of TH by follicle cells |
| sugars cannot be used as cellular fuel, more fats are mobilized resulting in high fatty acids levels in blood | lipidemia |
| chief cells are | found within the parathyroid gland that secrete parathyroid hormone |
| during cAMP mechanism, eventually GTP bound to G protein is __ to GDP, & G protein becomes inactive once again | hydrolyzed |
| aldosterone __ excretion of Na+ from body | reduces |
| where Na+ goes __ follows | water |
| glucagon, epinephrine, growth hormone, thyroxine, & glucocorticoids are all | hyperglycemia hormones |
| hollow, spherical, colloid-containing structure of the thyroid gland | follicles |
| excessive glucose in kidney filtrate act as __ __ resulting in polyuria | osmotic diuretic |
| homeostatic imbalance of diabetes mellitus would be due to the hormone deficiency/overproduction of | insulin deficiency |
| hormone that duodenum of small intestine produces | cholecystokinin |
| targets of calcitonin include | skeleton & bony matrix |
| in females, prolactin levels rise & fall in rhythm with __ blood levels | estrogen |
| act as tiny fuel sensors, secreting glucagon & insulin appropriately during fasting & fed states | alpha & beta cells |
| most T3 & T4 released immediately binds to transport proteins, most importantly | thyroxine-binding globulins (TBGs) |
| group of chemical substances including certain hormones & cholesterol; fat soluble & contain little oxygen | steroid |
| hormones may communicate with their target cells by direct __ __ | gene activation |
| hormone that stimulates production of red blood cells; protein hormones that signals bone marrow to increase RBC production | erythropoietin (EPO) |
| enhances reabsorption of Ca2+, as well as excretion of phosphate (PO43-) by kidneys | step 2 PTH |
| with exception of thyroid hormone, all __ __ hormones exert their signaling effects through intracellular second messengers | amino acid-based |
| activated insulin receptor provides docking sites for intracellular __ proteins | relay |
| targeting the skeleton, calcitonin inhibits __ activity, inhibiting bone reabsorption & release of Ca2+ from bony matrix | osteoclast |
| hyposecretory disease of adrenal cortex, generally involving a deficient output of both mineralocorticoids & glucocorticoids | Addison's disease |
| enteroendocrine cells release amines, like serotonin acting as paracrines, diffusing to & influencing nearby target cells without first | entering bloodstream |
| male & female gonads produce steroid sex hormones __ to those produced by adrenal cortical cells | identical |
| cortisol __ is associated with significant inflammatory & anti-immune effects | excess |
| __ __, main cells of immune system, mature in thymus gland, where they are stimulated by thymosin hormones | T lymphocytes |
| epinephrine, ACTH, FSH, LH, glucagon, PTH, TSH, & calcitonin are all hormones that | act via cAMP mechanisms |
| excessive thirst | polydipsia |
| have multiple targets & effects, ranging from raising blood pressure & increasing expulsive uterine contraction of birth to enhancing blood clotting, pain, & inflammation | prostaglandins |
