Exam 2 Ch. 45
61) Which of the following is not a category of endocrine gland stimulus? A) humoral B) hormonal C) neural D) enzyme
B
10) What is the mode of action of aspirin and ibuprofen? A) They inhibit the synthesis of prostaglandins. B) They inhibit the release of nitric oxide, a potent vasodilator. C) They block paracrine signaling pathways. D) They stimulate the release of oxytocin. E) They stimulate the release of endorphins.
A
17) For hormones that homeostatically regulate cellular functions, A) negative feedback typically regulates hormone secretion. B) the circulating level of a hormone is held constant through a series of positive feedback loops. C) both lipid-soluble hormones and water-soluble hormones bind to intracellular protein receptors. D) endocrine organs release their contents into the bloodstream via specialized ducts. E) it is impossible to also have neural regulation of that system.
A
18) Nitric oxide and epinephrine A) both function as neurotransmitters. B) both function as steroid hormones. C) are both involved in the "fight-or-flight" response. D) bind the same receptors. E) both cause a reduction in the blood levels of glucose.
A
22) The hypothalamus controls the anterior pituitary by means of A) releasing hormones. B) second messengers. C) third messengers. D) antibodies. E) pyrogens.
A
24) Oxytocin and ADH are produced by the ________ and stored in the ________. A) hypothalamus; neurohypophysis B) adenohypophysis; kidneys C) anterior pituitary; thyroid D) adrenal cortex; adrenal medulla E) posterior pituitary; anterior pituitary
A
25) The hypothalamus modulates hormone secretion by the anterior pituitary by means of A) peptide hormones. B) steroid hormones. C) electrical synapses. D) neurotransmitters. E) paracrine signals.
A
3) Which of the following is (are) true? A) Hormones regulate cellular functions, and negative feedback regulates hormone levels. B) The circulating level of a hormone is held constant through a series of positive feedback loops. C) Both lipid-soluble hormones and water-soluble hormones bind to intracellular protein receptors. D) Only A and D are true. E) A, B, and C are true.
A
34) Which of the following statements about endocrine glands is incorrect? A) The parathyroids regulate metabolic rate. B) The thyroid participates in blood calcium regulation. C) The pituitary participates in the regulation of the gonads. D) The adrenal medulla produces "fight-or-flight" responses. E) The pancreas helps to regulate blood sugar concentration.
A
36) Which hormone exerts antagonistic action to PTH (parathyroid hormone)? A) thyroxine B) epinephrine C) growth hormone D) calcitonin E) glucagon
A
37) Which endocrine disorder is correctly matched with the malfunctioning gland? A) diabetes insipidus and the posterior pituitary gland B) giantism and the posterior pituitary gland C) goiter and the adrenal medulla D) diabetes mellitus and the parathyroid glands E) dwarfism and the adrenal cortex
A
40) The endocrine glands include the A) parathyroid glands. B) salivary glands. C) sweat glands. D) sebaceous glands. E) gallbladder.
A
47) The amino acid tyrosine is a starting substrate for the synthesis of A) epinephrine. B) steroid hormones. C) parathyroid hormone. D) vitamin D. E) acetylcholine.
A
52) Which combination of gland and hormone would be linked to winter hibernation and spring reproduction in bears? A) pineal gland, melatonin B) hypothalamus gland, melatonin C) anterior pituitary gland, gonadotropin-releasing hormone D) pineal gland, estrogen E) posterior pituitary gland, thyroid-stimulating hormone
A
58) Which of the following endocrine structures is (are) not controlled by a tropic hormone from the anterior pituitary? A) pancreatic islet cells B) thyroid gland C) adrenal cortex D) ovaries E) testes
A
6) Based on their effects, which pair below could be considered antagonistic? A) prostaglandin F and nitric oxide B) growth hormone and ecdysone C) endocrine and exocrine glands D) hormones and target cells E) neurosecretory cells and neurotransmitters
A
66) Oxytocin ________. A) release is an example of a positive feedback control mechanism B) exerts its most important effects during menstruation C) is an adenohypophyseal secretion D) controls milk production
A
69) Gonadocorticoid(s) ________. A) production by the adrenal gland is insignificant compared with sex hormone release from the gonads during late puberty B) synthesized by the adrenal medulla are primarily androgens C) hypersecretion can result in adrenogenital syndrome, also called feminization D) secretion inhibition is highly dependent on a negative feedback loop involving ACTH
A
72) The ability of a specific tissue or organ to respond to the presence of a hormone is dependent on ________. A) the presence of the appropriate receptors on the cells of the target tissue or organ B) the membrane potential of the cells of the target organ C) nothingall hormones of the human body are able to stimulate any and all cell types because hormones are powerful and nonspecific D) the location of the tissue or organ with respect to the circulatory path
A
79) Thyroid hormone (a small iodinated amine) enters target cells in a manner similar to ________. A) steroid hormones, because both diffuse easily into target cells B) glucagon, because the structure of glucagon is similar to that of thyroid hormone C) growth hormone, because the thyroid works synergistically with thyroid hormone D) insulin, because insulin is a small peptide
A
93) Which of the following is true about calcium homeostasis? A) Parathyroid hormone is the single most important regulator of calcium levels in the blood. B) Increased calcitonin levels will cause increased blood calcium levels. C) Parathyroid hormone causes an increase in osteoblast activity. D) High calcium levels cause bone resorption.
A
20) Hormones from the hypothalamus affect the release of all of the following except A) prolactin. B) oxytocin. C) growth hormone. D) thyroid-stimulating hormone. E) adrenocorticotropic hormone
B
40) What happens when beta cells of the pancreas release insulin into the blood? A) Blood glucose levels rise to a set point and stimulate glucagon release. B) Body cells take up more glucose. C) The liver breaks down glycogen to glucose. D) Alpha cells are stimulated to release glucose into the blood. E) Both B and D are correct.
B
44) Analysis of a blood sample from a fasting individual who had not eaten for 24 hours would be expected to reveal high levels of A) insulin. B) glucagon. C) secretin. D) gastrin. E) glucose.
B
44) Which of the following glands is controlled directly by the hypothalamus or central nervous system but not the anterior pituitary? A) ovary B) adrenal medulla C) adrenal cortex D) testis E) thyroid
B
45) When the beta cells of the pancreas release insulin into the blood, A) the blood glucose levels rise to a set point and stimulate glucagon release. B) the skeletal muscles and the adipose cells take up glucose at a faster rate. C) the liver catabolizes glycogen. D) the alpha cells of the pancreas release glucose into the blood. E) the kidneys begin gluconeogenesis.
B
47) Which of the following hormones is (are) secreted by the adrenal gland in response to stress and promote(s) the synthesis of glucose from noncarbohydrate substrates? A) glucagon B) glucocorticoids C) epinephrine D) thyroxine E) ACTH
B
49) Which of the following hormone sequences is correct? A) LH → FSH → adrenal glands B) GnRH → FSH → ovaries C) CRH → ACTH → FSH → thyroid gland D) CRH → LH → testes E) GnRH → FSH → LH → pineal gland
B
51) In response to stress, the adrenal gland promotes the synthesis of glucose from noncarbohydrate substrates via the action of the steroid hormone A) glucagon. B) cortisol. C) epinephrine. D) thyroxine. E) ACTH.
B
52) Melatonin is secreted by A) the hypothalamus during the day. B) the pineal gland during the night. C) the autonomic nervous system during the winter. D) the posterior pituitary gland during the day. E) the thyroid gland during cold seasons.
B
58) Gluconeogenesis occurs in the liver due to the action of ________. A) insulin B) cortisol C) aldosterone D) secretin
B
66) An example of antagonistic hormones controlling homeostasis is A) thyroxine and parathyroid hormone in calcium balance. B) insulin and glucagon in glucose metabolism. C) progestins and estrogens in sexual differentiation. D) epinephrine and norepinephrine in fight-or-flight responses. E) oxytocin and prolactin in milk production.
B
67) ADH ________. A) promotes dehydration B) is inhibited by alcohol C) is produced in the adenohypophysis D) increases urine production
B
74) The neurohypophysis or posterior lobe of the pituitary gland is not a true endocrine gland because ________. A) it is unable to function as an endocrine tissue because it is actually part of the neural system due to its location B) it is only a hormone storage area that receives hormones from the hypothalamus for release C) it is strictly a part of the neural system and has little or nothing to do with hormonal release D) embryonically it was an endocrine tissue, but in the adult human it is no longer functional
B
75) An example of antagonistic hormones controlling homeostasis is A) thyroxine and parathyroid hormone in calcium balance. B) insulin and glucagon in glucose metabolism. C) progestins and estrogens in sexual differentiation. D) epinephrine and norepinephrine in fight-or-flight responses. E) oxytocin and prolactin in milk production.
B
82) The major targets of growth hormone are ________. A) the blood vessels B) bones and skeletal muscles C) the liver D) the adrenal glands
B
87) The most important regulator of electrolyte concentrations in extracellular fluids is ________. A) glucagon B) aldosterone C) insulin D) cortisol
B
97) In circumstances where the body requires prolonged or increased levels of a hormone, the DNA of target cells will specify the synthesis of more receptors on the surface of the cells of the target organ. This is known as ________. A) a reaction to a stressor B) up-regulation C) cellular affinity D) the cell's sensitivity reaction
B
11) Different body cells can respond differently to the same peptide hormones because A) different target cells have different sets of genes. B) each cell converts that hormone to a different metabolite. C) a target cell's response is determined by the components of its signal transduction pathways. D) the circulatory system regulates responses to hormones by routing the hormones to specific targets. E) the hormone is chemically altered in different ways as it travels through the circulatory system.
C
13) Why is it that some body cells respond differently to the same peptide hormones? A) Different target cells have different genes. B) Each cell knows how it fits into the body's master plan. C) A target cell's response is determined by the product of a signal transduction pathway. D) The circulatory system regulates responses to hormones by routing the hormones to specific targets. E) The hormone is chemically altered in different ways as it travels through the circulatory system.
C
15) Frequently, very few molecules of a hormone are required to affect changes in a target cell. This is because A) hormones are lipid-soluble and readily penetrate the membranes of the target cell. B) hormones are large molecules that remain in circulation for months and can repeatedly stimulate the same cell. C) the mechanism of hormonal action involves an enzyme cascade that amplifies the response to a hormone. D) the mechanism of hormonal action involves the rapid replication of the hormone within the target cell. E) the mechanism of hormonal action involves memory cells that have had prior contact with the hormone.
C
16) Why would a liver cell and a lung cell respond differently to the same steroid hormone? A) They have different receptor proteins within the cell. B) They have different acceptor proteins on the chromatin. C) Steroid hormones usually transmit signals that are antagonistic. D) The acceptor proteins are associated with different genes in the two kinds of cells. E) The hormone-receptor complex is transcribed and processed differently in the two kinds of cells.
C
21) During mammalian labor and delivery, the contraction of uterine muscles is enhanced by oxytocin. This is an example of A) a negative feedback system. B) a hormone that acts in an antagonistic way with another hormone. C) a hormone that is involved in a positive feedback loop. D) signal transduction immediately changing gene expression in its target cells. E) the key role of the anterior pituitary gland in regulating uterine contraction.
C
21) The endocrine system and the nervous system are structurally related. Which of the following cells best illustrates this relationship? A) a neuron in the spinal cord B) a steroid-producing cell in the adrenal cortex C) a neurosecretory cell in the hypothalamus D) a brain cell in the cerebral cortex E) a cell in the pancreas that produces digestive enzymes
C
23) Short blood vessels connect two capillary beds lying in which of the following? A) hypothalamus and thalamus B) anterior pituitary and posterior pituitary C) hypothalamus and anterior pituitary D) posterior pituitary and thyroid gland E) anterior pituitary and adrenal gland
C
24) The interrelationships between the endocrine and the nervous systems are especially apparent in A) a neuron in the spinal cord. B) a steroid-producing cell in the adrenal cortex. C) a neurosecretory cell in the hypothalamus. D) a brain cell in the cerebral cortex. E) a cell in the pancreas that produces digestive enzymes.
C
29) Prolactin stimulates mammary gland growth and development in mammals and regulates salt and water balance in freshwater fish. Many scientists think that this wide range of functions indicates that prolactin A) is a nonspecific hormone. B) has a unique mechanism for eliciting its effects. C) is an evolutionarily conserved hormone. D) is derived from two separate sources. E) interacts with many different receptor molecules.
C
42) The endocrine system and the nervous system are chemically related. Which of the following substances best illustrates this relationship? A) estrogen B) calcitonin C) norepinephrine D) calcium E) ecdysone
C
46) A chemical signal that has both endocrine and neural roles is A) parathyroid hormone. B) calcitonin. C) epinephrine. D) acetylcholine. E) ecdysone.
C
49) A disease that destroys the adrenal cortex should lead to an increase in the plasma levels of A) glucocorticoid hormones. B) epinephrine. C) adrenocorticotropic hormone (ACTH). D) glucose. E) acetylcholine.
C
69) Steroid and peptide hormones typically have in common A) the building blocks from which they are synthesized. B) their solubility in cell membranes. C) their requirement for travel through the bloodstream. D) the location of their receptors. E) their reliance on signal transduction in the cell.
C
74) Which of the following hormones is incorrectly paired with its action? A) oxytocin—stimulates uterine contractions during childbirth B) thyroxine—stimulates metabolic processes C) insulin—stimulates glycogen breakdown in the liver D) ACTH—stimulates the release of glucocorticoids by the adrenal cortex E) melatonin—affects biological rhythms, seasonal reproduction
C
77) A portal vessel carries blood from the hypothalamus directly to the A) thyroid. B) pineal gland. C) anterior pituitary. D) posterior pituitary. E) liver.
C
79) The main target organs for tropic hormones are A) muscles. B) blood vessels. C) endocrine glands. D) kidneys. E) nerves.
C
94) Aldosterone ________. A) presence increases potassium concentration in the blood B) is secreted by the neurohypophysis C) functions to increase sodium reabsorption D) production is greatly influenced by ACTH
C
99) A man has been told that he is not synthesizing enough follicle-stimulating hormone (FSH), and for this reason he may be unable to father a child. Choose the correct statement to explain this problem. A) The physician is wronga hormone made in the adenohypophysis could not influence fertility. B) The man must be producing progesterone, which inhibits the synthesis of FSH. C) FSH stimulates sperm production in the testes. D) FSH stimulates estrogen secretion by ovarian cells; therefore it is not synthesized by males.
C
101) Thyroxine is a peptide hormone, but its mechanism is different from other peptide hormones. Which of the following statements is true concerning this difference? A) It causes positive feedback. B) It is a stimulant of cellular metabolism and targets all cells. C) It is very specific in the cell type it targets. D) It does not require a second messenger to effect a response.
D
102) How do glucocorticoids enable the body to deal appropriately with stress? A) by stimulating the pancreas to release insulin B) by decreasing the heart rate, thus decreasing blood pressure C) by blocking the neurotransmitters that prepare the body for the stress response D) by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure
D
14) How is a cell's response to a water-soluble hormone amplified? A) regulation of intracellular hormone levels B) regulation of cell volume C) changes in the intracellular levels of cytokines D) regulatory proteins present inside of the cell E) regulation of the number of surface receptors
D
19) Where is it likely that you will find the receptor molecules for chemical signals? A) in the nucleus of target cells B) in the interstitial fluid surrounding target cells C) in the cytoplasm of target cells D) in the cell membrane of target cells E) associated with the DNA of target cells
D
26) Which of the following statements about the hypothalamus is incorrect? A) It functions as an endocrine gland. B) It is part of the central nervous system. C) It is subject to feedback inhibition by certain hormones. D) It secretes tropic hormones that act directly on the gonads. E) Its neurosecretory cells terminate in the posterior pituitary.
D
29) Which of the following have nontropic effects only? A) FSH B) LH C) TSH D) MSH E) ACTH
D
36) A tropic hormone from the anterior pituitary gland regulates the secretion of A) parathyroid hormone. B) calcitonin. C) epinephrine. D) thyroxine. E) glucagon.
D
38) All of the following are steroid hormones except A) androgen. B) cortisol. C) estrogen. D) insulin. E) testosterone.
D
39) Fight-or-flight reactions include activation of A) the parathyroid glands, leading to increased metabolic rate. B) the thyroid gland, leading to an increase in the blood calcium concentration. C) the anterior pituitary gland, leading to cessation of gonadal function. D) the adrenal medulla, leading to increased secretion of epinephrine. E) the pancreas, leading to a reduction in the blood sugar concentration.
D
4) What do nitric oxide and epinephrine have in common? A) They both function as neurotransmitters. B) They both function as hormones. C) They are both involved in the "fight-or-flight" response. D) Only A and B are correct. E) A, B, and C are correct.
D
41) The body's reaction to PTH (parathyroid hormone), a reduction in plasma levels of calcium, can be opposed by A) thyroxine. B) epinephrine. C) growth hormone. D) calcitonin. E) glucagon.
D
42) Which of the following has both endocrine and exocrine activity? A) the pituitary gland B) parathyroid glands C) salivary glands D) the pancreas E) adrenal glands
D
43) Linkage to membrane-bound receptor proteins on target cells activates the typical actions of the A) androgens. B) glucocorticoids. C) estrogens. D) pancreatic hormones. E) progestins.
D
5) Substance X is secreted by one cell, travels a short distance through interstitial fluid, and produces an effect in a cell immediately adjacent to the original secreting cell. All of the following terms could describe this substance except A) nitric oxide. B) neurotransmitter. C) prostaglandin. D) pheromone. E) growth factor.
D
50) Which of the following pairs of hormones do not have antagonistic effects? A) insulin and glucagon B) thyroid-releasing hormone and T3 and T4 C) parathyroid hormone and calcitonin D) follicle-stimulating hormone and luteinizing hormone E) aldosterone and atrial natriuretic factor
D
62) Epinephrine is an example of A) an androgen. B) an estrogen. C) a progestin. D) a catecholamine. E) a glucocorticoid.
D
63) Insect brain hormone is most analogous to which of the following in humans? A) insulin from the pancreas B) parathyroid hormone from the parathyroid gland C) ADH from the posterior pituitary D) releasing hormones from the hypothalamus E) androgens from the adrenal cortex
D
64) Which of the following is not a cardinal sign of diabetes mellitus? A) polyphagia B) polydipsia C) polyuria D) All of these are signs.
D
65) Which of the choices below is not a factor required for target cell activation by hormone receptor interaction? A) strength of the bond between the receptor and hormone B) blood levels of hormone C) number of receptor D) type of hormone
D
65) Which of the choices below is not a factor required for target cell activation by hormone receptor interaction? A) strength of the bond between the receptor and hormone B) blood levels of hormone C) number of receptors for that hormone D) type of hormone
D
66) Which of these is the second of the three stages of cell signaling? A) reception B) transduction C) gene activation D) binding of a neurotransmitter to a plasma membrane receptor E) cell response
D
67) Growth factors are local regulators that A) are produced by the anterior pituitary. B) are modified fatty acids that stimulate bone and cartilage growth. C) are found on the surface of cancer cells and stimulate abnormal cell division. D) bind to cell-surface receptors and stimulate growth and development of target cells. E) convey messages between nerve cells.
D
76) The second-messenger mechanism of hormone action operates by ________. A) synthesizing more of the hormone than is actually needed B) not responding to a feedback mechanism C) increasing the basal metabolic rate in the target organ D) binding to specific receptors and employing the services of G proteins and cAMP
D
83) The parathyroid glands maintain adequate levels of blood calcium. This is accomplished through ________. A) blocking the action of growth hormone B) slowing the activity of tissues that require calcium for activity C) antagonizing the synthesis of calcitonin D) targeting the bone and activating osteoclasts so that calcium will be released
D
17) For hormones that homeostatically regulate cellular functions, A) negative feedback typically regulates hormone secretion. B) the circulating level of a hormone is held constant through a series of positive feedback loops. C) both lipid-soluble hormones and water-soluble hormones bind to intracellular protein receptors. D) endocrine organs release their contents into the bloodstream via specialized ducts. E) it is impossible to also have neural regulation of that system.
E
20) Hormones that promote homeostasis A) are not found as members of antagonistic signaling mechanisms. B) travel to target cells without passage in the plasma. C) utilize receptors that bind any hormone. D) initiate signal transduction in the target cell without binding to receptors. E) usually operate as part of a negative feedback system.
E
28) The hypothalamus A) functions only as an endocrine target, by having lots of receptors on its cells. B) functions only in neuronal transmission. C) does not have any hormone receptors on its cells. D) secretes tropic hormones that act directly on the gonads. E) includes neurosecretory cells that terminate in the posterior pituitary.
E
39) Blood samples taken from an individual who had been fasting for 24 hours would have which of the following? A) high levels of insulin B) high levels of glucagon C) low levels of insulin D) low levels of glucagon E) both B and C
E
43) Which of the following are synthesized from the amino acid tyrosine? A) epinephrine B) catecholamines C) norepinephrine D) A and B only E) A, B, and C
E
55) After eating a carbohydrate-rich meal, the mammalian pancreas increases its secretion of A) ecdysone. B) glucagon. C) thyroxine. D) oxytocin. E) insulin.
E
68) The primary reason steroid hormones usually act slowly is that A) target cells tend to ignore steroid hormones in favor of nonsteroid hormones. B) they are produced at very low concentrations. C) they are too large to enter a cell and therefore must first bind to a plasma membrane receptor before having an effect on a cell. D) acting via a signal transduction pathway makes for slower responses than does directly interacting with a cell's DNA. E) they turn genes on or off and it takes time for gene products to build up or become depleted.
E
57) All adenohypophyseal hormones except GH affect their target cells via a cyclic AMP second messenger.
True
102) How do glucocorticoids enable the body to deal appropriately with stress? A) by stimulating the pancreas to release insulin B) by decreasing the heart rate, thus decreasing blood pressure C) by blocking the neurotransmitters that prepare the body for the stress response D) by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure
d