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1. Which of the following statements is not true of the endocrine system? (2.0 分)A.It is one of
two major regulatory systems of the body.
B.It is composed of glands that secrete chemical messengers into the blood.
C.It is an important regulator of homeostatic mechanisms.
D.It influences and is influenced by the nervous system.
E.All of the choices are true.
2. Hormones (2.0 分)A.are chemical regulators that are conveyed from one organ to another via
the blood stream.
B.in some cases, also function as local regulators and/or neurotransmitters.
C.in some cases, contain carbohydrates.
D.Both are chemical regulators that are conveyed from one organ to another via the blood stream
and, in some cases, also function as local regulators and/or neurotransmitters are correct.
E.All of the choices are correct.
3. An endocrine cell that contains an abundance of granular endoplasmic reticulum, a large Golgi
apparatus, and secretion granules is likely to (2.0 分)A.secrete a peptide/protein hormone.
B.secrete by exocytosis.
C.secrete in an exocrine manner.
D.secrete a peptide/protein hormone and secrete by exocytosis.
E.do all of these things.
4. Cells that secrete steroid hormones (2.0 分)A.store large amounts of hormone.
B.are characterized by abundant agranular endoplasmic reticulum.
C.are characterized by large and numerous mitochodria.
D.Both store large amounts of hormone and are characterized by abundant agranular endoplasmic
reticulum are correct.
E.Both are characterized by abundant agranular endoplasmic reticulum and are characterized by
large and numerous mitochondria are correct.
5. Regarding the structure and synthesis of hormones, (2.0 分)A.steroid hormones are synthesized
from cholesterol.
B.thyroid hormones are catecholamines.
C.the hormones of the adrenal cortex have the same structure as the neurotransmitters of
adrenergic neurons.
D.most peptide hormones require binding proteins for transport in the blood.
E.vasopressin is synthesized in the posterior pituitary.
6. The enzyme in the mitochondria responsible for the modification of cholesterol that is
important to the synthesis of steroid hormones is called (2.0 分)A.cytochrome P450 enzymes.
B.tyrosine hydroxylase.
C.protein kinase.
D.cholesterol esterase.
E.lipase.
7. Which of the following statements about hormone activation is true? (2.0 分)A.Prohormones are
inactive messengers that must undergo conversion to an active form at their site of production.
B.Conversion of T3 to T4 is an example of hormone activation.
C.Conversion of testosterone to estradiol is an example of hormone activation.
D.Both prohormones are inactive messengers that must undergo conversion to an active form at
their site of production and conversion of T3 to T4 is an example of hormone activation are true.
E.Both prohormones are inactive messengers that must undergo conversion to an active form at
their site of production and conversion of testosterone to estradiol is an example of hormone
activation are true.
8. Which of the following statements about hormone synthesis is not correct? (2.0
分)A.Progesterone is a precursor of cortisol.
B.Progesterone is a precursor of mineralcorticoid(s) and glucocorticoid(s).
C.Progesterone is a precursor for all steroid hormones.
D.Tryptophan is a precursor for thyroid hormones.
E.All of these are true statements.
9. If a patient were given a drug that inhibited the actions of proteolytic enzymes in the blood
plasma only (i.e., not in cells), which of the following is most likely to result? (2.0
分)A.Conversion of thyroxine to triiodothyronine would be inhibited.
B.Conversion of angiotensinogen to angiotensin would be reduced.
C.Conversion of testosterone to estradiol would be unaffected.
D.Both conversion of thyroxine to triiodothyronine would be inhibited and conversion of
angiotensinogen to angiotensin would be reduced would result.
E.Both conversion of angiotensinogen to angiotensin would be reduced and conversion of
testosterone to estradiol would be unaffected would result.
10. Peptide hormones are (2.0 分)A.often derived from larger molecules called prohormones.
B.packaged into secretory vesicles in the endoplasmic reticulum of the cells that synthesize them.
C.secreted in response to a stimulus that causes depletion of cytosolic calcium in the secreting
cell.
D.Both often derived from larger molecules called prohormones and packaged into secretory
vesicles in the endoplasmic reticulum of the cells that synthesize them are correct.
E.Both often derived from larger molecules called prohormones and secreted in response to a
stimulus that causes depletion of cytosolic calcium in the secreting cell are correct.
11. A hormone may be (2.0 分)A.inactivated by its target cell.
B.activated by its target cell.
C.inactivated by nontarget cells.
D.excreted before it has a chance to act on a target cell.
E.All of the choices are correct.
12. The concentration of a hormone in plasma is determined by (2.0 分)A.its secretion and
clearance rates.
B.whether or not it binds to carriers and/or other plasma proteins.
C.the kind of receptor to which it binds.
D.its secretion and clearance rates and whether or not it binds to carriers and/or other plasma
proteins.
E.whether or not it binds to carriers and/or other plasma proteins and the kind of receptor to which
it binds.
13. Some hormones are transported in plasma bound to proteins. These proteins function to (2.0
分)A.maintain a stable high concentration of the hormone in the plasma and reduce its clearance
rate from plasma.
B.reduce the binding of the hormone to its receptors in some cases.
C.make the hormone more soluble in aqueous plasma.
D.do all of these things.
E.do none of these things.
14. The liver participates in endocrine regulation by (2.0 分 )A.producing hormones and
hormone-binding proteins.
B.clearing hormones from plasma.
C.secreting an inactive form of a hormone that is activated in the plasma.
D.doing producing hormones and hormone-binding proteins and clearing hormones from plasma.
E.doing all of these things.
15. The main difference between the modes of action of peptide hormones and steroid hormones is
that (2.0 分)A.peptide hormones bind to intracellular receptors whereas steroid hormones bind to
receptors on the cell surface.
B.peptide hormones bind to receptors in the nucleus whereas steroid hormones bind to receptors in
the cytosol.
C.peptide hormones bind to receptors on the cell surface whereas steroid hormones act as second
messengers.
D.peptide hormones bind to receptors on the cell surface whereas steroid hormones bind to
intracellular receptors.
E.there are no differences; both act by binding to receptors on the cell surface.
16. Receptors for steroid hormones (2.0 分)A.are proteins in the nucleus and/or cytoplasm.
B.undergo allosteric modulation when they bind to the hormone.
C.regulate gene transcription.
D.Both are proteins in the nucleus and/or cytoplasm and regulate gene transcription are correct.
E.All of the choices are correct.
17. Rapidly acting chemical regulators generally (2.0 分)A.bind to receptor proteins in the nucleus
of target cells.
B.are polar.
C.activate plasma-membrane-associated receptors.
D.Both bind to receptor proteins in the nucleus of target cells and are polar are correct.
E.Both are polar and activate plasma-membrane-associated receptors are correct.
18. In the absence of thyroid hormone, epinephrine stimulates release of a small amount of fatty
acids from adipose cells. In the presence of thyroid hormone (which has no effect by itself),
epinephrine causes a much more substantial release of fatty acids fr(2.0 分)A.antagonistic.
B.agonistic.
C.permissive.
D.direct.
E.paracrine.
19. Secretion of hormones is controlled by (2.0 分)A.concentration of mineral ions in the blood.
B.neural input.
C.tropic hormones.
D.concentration of mineral ions in the blood and tropic hormones.
E.all of these things.
20. Which of the following is not a cause of hyporesponsiveness? (2.0 分)A.low levels of the
circulating hormone
B.abnormal receptors incapable of binding the hormone on the target tissue
C.defects in the second messenger pathway used by a hormone and its receptor
D.enzymes required for activation of the prohormone may be absent
E.All of the choices are causes of hyporesponsiveness.
21. Which of the following hormones is not secreted by the anterior pituitary gland? (2.0
分)A.somatotropin
B.prolactin
C.corticotropin
D.erythropoietin
E.TSH
22. The "master gland" of the endocrine system is the (2.0 分)A.anterior pituitary gland.
B.posterior pituitary gland.
C.hypothalamus.
D.pancreas.
E.testis.
23. Examples of long-loop negative feedback include (2.0 分)A.the stimulation of dopamine
release by prolactin.
B.inhibition of GHRH release by GH.
C.inhibition of GHRH release by IGF-I.
D.the stimulation of dopamine release by prolactin and inhibition of GHRH release by GH.
E.inhibition of GHRH release by GH and inhibition of GHRH release by IGF-I.
24. Which of the following statements is correct? (2.0 分)A.Anterior pituitary hormones are
synthesized in the hypothalamus.
B.All hormones secreted by the anterior and posterior pituitary glands are peptides.
C.IGF-I stimulates growth by increasing growth hormone secretion through positive feedback.
D.Both anterior pituitary hormones are synthesized in the hypothalamus and all hormones secreted
by the anterior and posterior pituitary glands are peptides are correct.
E.Both all hormones secreted by the anterior and posterior pituitary glands are peptides and IGF-I
stimulates growth by increasing growth hormone secretion through positive feedback are correct.
25. The precursor for cortisol is ________ , which is made from ________. Cortisol is secreted by
________ when stimulated by ________ from the anterior pituitary. (2.0 分)A.androstenedione,
progesterone, adrenal cortex, crh
B.progesterone, cholesterol, adrenal medulla, acth
C.testosterone, cholesterol, adrenal medulla, acth
D.progesterone, cholesterol, adrenal cortex, acth
E.estrogen, cholesterol, adrenal medulla, crh
26. The posterior pituitary (2.0 分)A.synthesizes oxytocin and vasopressin.
B.is neural tissue.
C.secretes hormones when stimulated by action potentials generated in the hypothalamus.
D.Both synthesizes oxytocin and vasopressin and is neural tissue are correct.
E.Both is neural tissue and secretes hormones when stimulated by action potentials generated in
the hypothalamus are correct.
27. The gonadotropic hormones (2.0 分)A.stimulate hormone secretion by the gonads.
B.are secreted by the anterior pituitary gland of both males and females.
C.are LH and prolactin.
D.Both stimulate hormone secretion by the gonads and are secreted by the anterior pituitary gland
of both males and females are correct.
E.All of the choices are correct.
28. If the adrenal glands were removed from a patient, his plasma cortisol levels would ________
and secretion of ________ by the adenohypophysis would ________ because the ________ would
secrete ________ amounts of the regulator ________. This last effect wo(2.0 分)A.increase; TSH;
increase; brain; reduced; ACTH; equilibrium
B.decrease; ACTH; increase; hypothalamus; increased; CRH; negative feedback
C.decrease; CRH; remain stable; hypothalamus; reduced; ACTH; negative feedback
D.decrease; ACTH; increase; hypothalamus; increased; CRH; positive feedback
E.decrease; ACTH; increase; hypothalamus; increased; CRH; plasma electrolytes in the urine
29. Hypertrophy of the adrenal cortex could result from (2.0 分)A.excessively rapid clearance of
cortisol from the circulation.
B.a tumor of the pituitary gland that secretes excessive amounts of ACTH.
C.inactivation of enzymes that are required to synthesize corticosteroids.
D.excessively rapid clearance of cortisol from the circulation and a tumor of the pituitary gland
that secretes excessive amounts of ACTH.
E.All of the choices are correct.
30. A subject consuming a diet deficient in iodine is likely to have (2.0 分)A.a low plasma
concentration of thyroxine due to reduced secretion of TSH by the pituitary gland.
B.a low plasma concentration of thyroxine and an enlarged thyroid gland.
C.a high plasma concentration of TSH.
D.a low plasma concentration of thyroxine due to reduced secretion of TSH by the pituitary gland
and a low plasma concentration of thyroxine and an enlarged thyroid gland.
E.a low plasma concentration of thyroxine and an enlarged thyroid gland and a high plasma
concentration of TSH.
31. What would be the effect of a blood clot that blocked the veins of the hypothalamo-pituitary
portal system in the infundibulum between the hypothalamus and the anterior pituitary gland? (2.0
分)A.Secretion of ACTH will decrease and the adrenal cortex will atrophy.
B.The secretion of gonadotropins will decrease and the gonads will hypertrophy.
C.Plasma cortisol concentration will decrease, which will cause a decrease in long-loop negative
feedback, and so the secretion of ACTH by the pituitary gland will increase.
D.Both secretion of ACTH will decrease and the adrenal cortex will atrophy and The secretion of
gonadotropins will decrease and the gonads will hypertrophy would occur.
E.Both the secretion of gonadotropins will decrease and the gonads will hypertrophy and Plasma
cortisol concentration will decrease, which will cause a decrease in long-loop negative feedback,
and so the secretion of ACTH by the pituitary gland will increas
32. Exposure to stress activates the hypothalamo-pituitary-adrenocortical system as demonstrated
by (2.0 分)A.increased secretion of corticotropin from the anterior pituitary in response to stress.
B.increased secretion of corticotropin releasing hormone from the hypothalamus in response to
stress.
C.increased secretion of cortisol from the adrenal medulla in response to stress.
D.increased secretion of corticotropin from the anterior pituitary in response to stress and
increased secretion of corticotropin releasing hormone from the hypothalamus in response to
stress.
E.All of the choices are correct.
33. If the pituitary gland is removed from a human subject, which of the following is likely to
occur? (2.0 分)A.The adrenal gland will hypertrophy to increase cortisol production.
B.The adrenal gland will atrophy and plasma cortisol levels will be reduced.
C.The hypothalamus will secrete less CRH.
D.The subject will remain euthyroid.
E.None of these things are likely to occur.
34. The hormones secreted by the posterior pituitary include (2.0 分)A.vasopressin.
B.corticotropin.
C.oxytocin.
D.vasopressin and corticotropin.
E.vasopressin and oxytocin.
35. Stimuli for the secretion of growth hormone include (2.0 分)A.waking from sleep.
B.exercising.
C.increased levels of IGF-I in blood.
D.waking from sleep and exercising.
E.exercising and increased levels of IGF-I in blood.
36. Deficiency of iodine in the diet results in a goiter (an enlarged thyroid gland). Which of the
following statements offers the best explanation for this phenomenon? (2.0 分)A.The thyroid
enlarges so that it can secrete more thyroid hormones to compensate for the lack of iodine.
B.Decreased plasma iodine levels are detected by the hypothalamus, which stimulates the anterior
pituitary to secrete more thyroid stimulating hormone.
C.Without iodine, the thyroid gland cannot produce thyroid hormones. Thyroid hormones
normally act as a negative-feedback signal for the hypothalamus and pituitary gland. Loss of this
signal results in excessive secretion of thyroid stimulating hormone.
D.All of the choices are correct.
E.None of the choices are correct.
37. To synthesize thyroid hormones, iodine is attached to (2.0 分)A.cholesterol.
B.the amino acid tyrosine.
C.the amino acid tryptophan.
D.acetyl coenzyme A.
E.the amino acid phenylalanine.
38. Thyroid hormones stimulate metabolism by stimulating (2.0 分)A.lipid synthesis.
B.the Na/K ATPase.
C.action potentials.
D.cell division.
39. An absence of thyroid hormones during fetal development leads to (2.0 分)A.acromegaly.
B.Cushing's Syndrome.
C.cretinism.
D.Grave's disease.
E.Addison's disease.
40. Stress (2.0 分)A.refers to a wide variety of noxious stimuli.
B.invariably results in aldosterone secretion by the adrenal cortex.
C.usually activates the parasympathetic nervous system.
D.Both refers to a wide variety of noxious stimuli and invariably results in aldosterone secretion
by the adrenal cortex are correct.
E.Both refers to a wide variety of noxious stimuli and usually activates the parasympathetic
nervous system are correct.
41. During stress, cortisol (2.0 分)A.stimulates protein synthesis.
B.antagonizes the actions of insulin.
C.increases glucose availability to the brain.
D.Both stimulates protein synthesis and antagonizes the actions of insulin are correct.
E.Both antagonizes the actions of insulin and increases glucose availability to the brain are
correct.
42. Which of the following statements regarding activation of the sympathetic nervous system
during stress is true? (2.0 分)A.It increases one's ability to respond to situations where physical
activity is required.
B.It increases blood flow to the skeletal muscles and viscera.
C.It inhibits blood clotting.
D.Both it increases one's ability to respond to situations where physical activity is required and it
increases blood flow to the skeletal muscles and viscera are true.
E.Both it increases one's ability to respond to situations where physical activity is required and it
inhibits blood clotting are true.
43. During stress, (2.0 分)A.insulin secretion is stimulated and glucagon secretion is inhibited.
B.hormones that decrease salt and water excretion are secreted.
C.prolactin and growth hormone are co-secreted from the anterior pituitary with ACTH.
D.both insulin secretion is stimulated and glucagon secretion is inhibited and hormones that
decrease salt and water excretion are secreted occur.
E.both hormones that decrease salt and water excretion are secreted and prolactin and growth
hormone are co-secreted from the anterior pituitary with ACTH occur.
44. Bone growth (2.0 分)A.occurs as a result of osteoblast division.
B.of the long bones requires growth of the epiphyseal cartilage.
C.of the long bones ceases after closure of the epiphyseal growth plate.
D.Both occurs as a result of osteoblast division and of the long bones requires growth of the
epiphyseal cartilage are correct.
E.Both of the long bones requires growth of the epiphyseal cartilage and of the long bones ceases
after closure of the epiphyseal growth plate are correct.
45. In order for growth to occur, (2.0 分)A.anabolism must exceed catabolism.
B.catabolism must exceed anabolism.
C.anabolism and catabolism must be evenly balanced.
D.plasma levels of growth hormone must exceed those of insulin.
E.None of the choices are correct.
46. Which of the following is true regarding pituitary growth hormone? (2.0 分)A.The liver
produces a factor that mediates the metabolic actions of GH.
B.GH stimulates IGF-I production by the liver and by many other cells.
C.GH has diabetogenic activity.
D.Both the liver produces a factor that mediates the metabolic actions of GH and GH stimulates
IGF-I production by the liver and by many other cells are true.
E.Both GH stimulates IGF-I production by the liver and by many other cells and GH has
diabetogenic activity are true.
47. Which of the following is not true of pituitary growth hormone? (2.0 分)A.It directly promotes
protein anabolism in many cells.
B.It causes differentiation of precursor cells that then respond to IGF-I by proliferating.
C.Hypersecretion of growth hormone in adults leads to acromegaly.
D.It is absent or deficient in pituitary dwarfs.
E.It is necessary for fetal growth.
48. Thyroid hormones are important for growth because they (2.0 分 )A.maintain the
responsiveness of various tissues to growth-promoting hormones.
B.promote synthesis of GH by the anterior pituitary gland.
C.increase metabolic rate above normal when their levels are high.
D.Both do maintain the responsiveness of various tissues to growth-promoting hormones and
promote synthesis of GH by the anterior pituitary gland are correct.
E.do all of the choices.
49. A deficiency in dietary iodine can cause (2.0 分)A.cretinism.
B.a slowing of mental functions.
C.low metabolic rate.
D.cretinism and a slowing of mental functions.
E.all of these things.
50. Estrogen in females and testosterone in males (2.0 分)A.are responsible for the pubertal
growth spurt.
B.are responsible for epiphyseal plate closure.
C.cause increased strength and mass of skeletal muscle.
D.Both are responsible for the pubertal growth spurt and are responsible for epiphyseal plate
closure are correct.
E.All of the choices are correct.