1) All hormones
A) are produced by endocrine glands.
B)
are lipid-soluble molecules.
C) are carried to target cells in
the blood.
D) are protein molecules.
E) elicit the same
biological response from all of their target cells.
Answer: C
2) In a positive-feedback system where hormone A alters the amount of
protein X
A) an increase in A always produces an increase in X.
B) an increase in X always produces a decrease in A.
C) a
decrease in A always produces an increase in X.
D) a decrease in
X always causes a decrease in A.
E) it is impossible to predict
how A and X affect each other.
Answer: A
3) Testosterone is an example of a chemical signal that affects the
very cells that synthesize it, the neighboring cells in the testis,
along with distant cells outside the gonads. Thus, testosterone is an
example of
A) an autocrine signal.
B) a paracrine signal.
C) an endocrine signal.
D) both an autocrine signal and a
paracrine signal.
E) an autocrine signal, a paracrine signal,
and an endocrine signal.
Answer: E
4) Which category of signal exerts its effects on target cells by
binding to membrane-bound receptor proteins?
A) neurohormones
B) estrogens
C) androgens
D) vitamin D
E)
neurohormones, estrogens, androgens, and vitamin D
Answer: A
5) A paracrine signal that relaxes smooth muscle cells is
A)
nitric oxide.
B) vitamin D.
C) testosterone.
D)
cortisol.
E) antidiuretic hormone.
Answer: A
6) Prostaglandins are local regulators whose chemical structure is
derived from
A) oligosaccharides.
B) fatty acids.
C)
steroids.
D) amino acids.
E) nitric oxide.
Answer: B
7) Ecdysone is a(n)
A) peptide hormone.
B) amine
derivative.
C) steroid hormone.
D) iodinated protein
hormone made by the thyroid gland.
E) gaseous neurotransmitter.
Answer: C
8) Aspirin and ibuprofen both
A) inhibit the synthesis of
prostaglandins.
B) inhibit the release of nitric oxide, a potent
vasodilator.
C) activate the paracrine signaling pathways that
form blood clots.
D) stimulate the release of oxytocin.
E)
stimulate vasoconstriction in the kidneys.
Answer: A
9) A cell with membrane-bound proteins that selectively bind a
specific hormone is called that hormone's
A) secretory cell.
B) plasma cell.
C) endocrine cell.
D) target cell.
E) regulatory cell.
Answer: D
10) The reason that the steroid hormone aldosterone affects only a
small number of cells in the body is that
A) only its target
cells get exposed to aldosterone.
B) only its target cells
contain aldosterone receptors.
C) it is unable to enter
nontarget cells.
D) nontarget cells destroy aldosterone before
it can produce any effect.
E) nontarget cells convert
aldosterone to a hormone to which they do respond.
Answer: 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.
Answer: C
<p>12) Insect hormones and their receptors <br>A) act independently of each other. <br>B) are a focus in pest-control research. <br>C) utilize cell-surface receptors only. <br>D) are active independently of environmental cues. <br>E) are not relevant to the study of steroid hormones.</p> <p>12) Insect hormones and their receptors <br>A) act independently of each other. <br>B) are a focus in pest-control research. <br>C) utilize cell-surface receptors only. <br>D) are active independently of environmental cues. <br>E) are not relevant to the study of steroid hormones.</p>
Answer: B
13) Endocrine glands that are sources of steroid hormones
A)
secrete the steroids through ducts into the blood.
B) store
those hormones in membrane-bound vesicles.
C) have a very short
latency between steroid synthesis and steroid release.
D) are
all controlled by the autonomic nervous system.
E) operate
independently of other hormonal cuing systems.
Answer: C
14) A chemical signal operating in a paracrine manner is one that
A) is active at a neuronal synapse.
B) affects only the
cells that synthesize the paracrine signal.
C) requires
transport in the blood before it can act on its target cells.
D)
evokes responses from all parts of the vascular system.
E) must
move through the air before it reaches its target cells.
Answer: A
15) Hormone X activates the cAMP second messenger system in its
target cells. The greatest response by a cell would come from
A)
applying a molecule of hormone X to the extracellular fluid
surrounding the cell.
B) injecting a molecule of hormone X into
the cytoplasm of the cell.
C) applying a molecule of cAMP to the
extracellular fluid surrounding the cell.
D) injecting a
molecule of cAMP into the cytoplasm of the cell.
E) injecting a
molecule of activated, cAMP-dependent protein kinase into the
cytoplasm of the cell.
Answer: A
16) When a steroid hormone and a peptide hormone exert similar
effects on a population of target cells, then
A) the steroid and
peptide hormones must use the same biochemical mechanisms.
B)
the steroid and peptide hormones must bind to the same receptor
protein.
C) the steroid hormones affect the synthesis of
effector proteins, whereas peptide hormones activate effector proteins
already present in the cell.
D) the steroid hormones affect the
activity of certain proteins within the cell, whereas peptide hormones
directly affect the processing of mRNA.
E) the steroid hormones
affect only the release of proteins from the target cell, whereas
peptide hormones affect only the synthesis of proteins that remain in
the target cell.
Answer: C
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.
Answer: 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.
Answer: A
19) Suppose that substance X is secreted by one cell, travels via
interstitial fluid to a neighboring cell, and produces an effect on
that cell. All of the following terms could describe this substance
except
A) paracrine signal.
B) neurotransmitter.
C)
prostaglandin.
D) pheromone.
E) growth factor.
Answer: D
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.
Answer: E
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.
Answer: C
22) During short-term starvation, most available fuel molecules are
catabolized to provide energy for metabolism rather than being used as
building blocks for growth and repair, a trade-off that is hormonally
regulated by
A) acetylcholine.
B) glucagon.
C)
oxytocin.
D) antidiuretic hormone.
E) insulin.
Answer: B
23) Based on their effects, which pair below would not be expected to
be active at the same time and place?
A) prostaglandin F and
nitric oxide
B) growth hormone and insulin-like growth factors
C) endocrine and exocrine glands
D) hormones and target
cells
E) neurosecretory cells and neurotransmitters
Answer: A
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.
Answer: C
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.
Answer: A
26) Portal blood vessels connect two capillary beds found in the
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.
Answer: C
27) If a person loses a large amount of water in a short period of
time, he or she may die from dehydration. ADH can help reduce water
loss through its interaction with its target cells in the
A)
anterior pituitary.
B) posterior pituitary.
C) adrenal
gland.
D) bladder.
E) kidney.
Answer: 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.
Answer: E
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.
Answer: C
<p>30) A product of the anterior pituitary gland that causes color changes in its target cells is <br>A) FSH. <br>B) LH. <br>C) TSH. <br>D) MSH. <br>E) ACTH.</p>
Answer: D
31) To prevent insect pests from maturing into reproducing adults,
pest controllers use synthetic agonists of
A) ecdysone.
B)
juvenile hormone.
C) oxytocin.
D) brain hormone.
E)
prothoracic hormone.
Answer: B
32) In a lactating mammal, the two hormones that promote milk
synthesis and milk release, respectively, are
A) prolactin and
calcitonin.
B) prolactin and oxytocin.
C)
follicle-stimulating hormone and luteinizing hormone.
D)
luteinizing hormone and oxytocin.
E) prolactin and luteinizing hormone.
Answer: B
33) Oxytocin and antidiuretic hormone are synthesized in the
A)
hypothalamus.
B) adenohypophysis.
C) anterior pituitary.
D) adrenal cortex.
E) posterior pituitary.
Answer: A
34) Endocrine structures derived from nervous tissue include the
A) thymus and the thyroid.
B) ovaries and the testes.
C) liver and the pancreas.
D) anterior pituitary gland and
the adrenal cortex.
E) posterior pituitary gland and the adrenal medulla.
Answer: E
35) Iodine is added to table salt to help prevent deficiencies of an
essential mineral needed for the proper function of the
A)
parathyroid glands.
B) adrenal glands.
C) thyroid glands.
D) the endocrine pancreas.
E) the exocrine pancreas.
Answer: C
36) A tropic hormone from the anterior pituitary gland regulates the
secretion of
A) parathyroid hormone.
B) calcitonin.
C) epinephrine.
D) thyroxine.
E) glucagon.
Answer: D
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
Answer: A
38) One reason a person might be severely overweight is due to
A) an undersecretion of thyroxine.
B) a defect in hormone
release from the posterior pituitary.
C) a lower than normal
level of insulin-like growth factors.
D) hyposecretion of
oxytocin.
E) a higher than normal level of melatonin.
Answer: A
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.
Answer: D
40) The endocrine glands include the
A) parathyroid glands.
B) salivary glands.
C) sweat glands.
D) sebaceous
glands.
E) gallbladder.
Answer: A
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.
Answer: 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
Answer: 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.
Answer: D
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.
Answer: 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.
Answer: B
46) A chemical signal that has both endocrine and neural roles is
A) parathyroid hormone.
B) calcitonin.
C)
epinephrine.
D) acetylcholine.
E) ecdysone.
Answer: C
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.
Answer: A
48) The autonomic nervous system includes an endocrine gland known as
the
A) ovary.
B) adrenal medulla.
C) adrenal cortex.
D) testis.
E) thyroid.
Answer: B
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.
Answer: C
50) During a stressful interval
A) TSH stimulates the adrenal
cortex and medulla to secrete acetylcholine.
B) the alpha cells
of islets secrete insulin and simultaneously the beta cells of the
islets secrete glucagon.
C) ACTH stimulates the adrenal cortex,
and neurons of the sympathetic nervous system stimulate the adrenal
medulla.
D) the posterior pituitary gland secretes more growth
hormones.
E) the calcium levels in the blood are increased due
to actions of two antagonistic hormones, epinephrine and norepinephrine.
Answer: C
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.
Answer: 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.
Answer: B
53) Winter hibernation and spring reproduction in bears are cued by
seasonal changes in the secretion of
A) melatonin from the
pineal gland.
B) melatonin from the hypothalamus.
C)
thyroxine from the anterior pituitary gland.
D) acetylcholine
from the pineal gland.
E) thyroid-stimulating hormone from the
posterior pituitary gland.
Answer: A
54) The steroid hormone that coordinates molting in arthropods is
A) ecdysone.
B) glucagon.
C) thyroxine.
D)
oxytocin.
E) growth hormone.
Answer: A
55) After eating a carbohydrate-rich meal, the mammalian pancreas
increases its secretion of
A) ecdysone.
B) glucagon.
C) thyroxine.
D) oxytocin.
E) insulin.
Answer: E
56) The higher level of metabolic activity typical of nonhibernating
temperate mammals during the winter months is due to increased
secretion of
A) ecdysone.
B) glucagon.
C) thyroxine.
D) oxytocin.
E) growth hormone.
Answer: C
57) The increased contraction of the human uterus during labor and
delivery is at least partially due to the actions of
A)
ecdysone.
B) glucagon.
C) thyroxine.
D) oxytocin.
E) growth hormone.
Answer: D
58) Abnormally reduced somatic growth (dwarfism) can be a consequence
of decreased hormone secretion from the
A) kidneys.
B)
pancreas.
C) adrenal gland.
D) posterior pituitary gland.
E) anterior pituitary gland.
Answer: E
59) DES is called an "endocrine disrupting chemical"
because it structurally resembles, and interferes with, the endocrine
secretions of the
A) pancreatic islet cells.
B) thyroid
gland.
C) adrenal medulla.
D) ovaries.
E) hypothalamus.
Answer: D
60) Testosterone is an example of
A) an androgen.
B) an
estrogen.
C) a progestin.
D) a catecholamine.
E) an
adrenal steroid.
Answer: A
61) Estradiol is an example of
A) an androgen.
B) an
estrogen.
C) a progestin.
D) a catecholamine.
E) a glucocorticoid.
Answer: B
62) Epinephrine is an example of
A) an androgen.
B) an
estrogen.
C) a progestin.
D) a catecholamine.
E) a glucocorticoid.
Answer: D
63) In an experiment, rats' ovaries were removed immediately after
impregnation and then the rats were divided into two groups.
Treatments and results are summarized in the table. The results most
likely occurred because progesterone exerts an effect on the
A)
general health of the rat.
B) size of the fetus.
C)
metabolism of the uterus.
D) gestation period of rats.
E)
number of eggs fertilized.
Answer: C
64) A fantasy movie features a caterpillar that never matures into an
adult, but simply gets larger and larger with each molt. It might be
possible that the caterpillar did not mature into an adult because of
A) a lack of ecdysone.
B) a lack of juvenile hormone.
C) a decreased level of ecdysone.
D) an increased level of
juvenile hormone.
E) a lack of melatonin.
Answer: D
65) Which of the following is not an accurate statement?
A)
Hormones are chemical messengers that travel to target cells through
the circulatory system.
B) Hormones often regulate homeostasis
through antagonistic functions.
C) Hormones of the same chemical
class usually have the same function.
D) Hormones are secreted
by specialized cells usually located in endocrine glands.
E)
Hormones are often regulated through feedback loops.
Answer: C
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.
Answer: B
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.
Answer: D
68) Which hormone is incorrectly paired with its action?
A)
oxytocinstimulates uterine contractions during childbirth
B)
thyroxinestimulates metabolic processes
C) insulinstimulates
glycogen breakdown in the liver
D) ACTHstimulates the release
of glucocorticoids by the adrenal cortex
E) melatoninaffects
biological rhythms, seasonal reproduction
Answer: 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.
Answer: C
70) Which of the following is the most likely explanation for
hypothyroidism in a patient whose iodine level is normal?
A)
greater production of T₃ than of T₄
B) hyposecretion of TSH
C) hypersecretion of TSH
D) hypersecretion of MSH
E)
a decrease in the thyroid secretion of calcitonin
Answer: B
71) Shortly after ingesting a big plate of carbohydrate-rich pasta,
you measure your blood's hormone levels. What results would you
expect, compared to before the meal?
A) high insulin, low
glucagon
B) low insulin, low glucagon
C) high insulin,
high glucagon
D) low insulin, high glucagon
E) low
insulin, no change in glucagon
Answer: A
72) The relationship between the insect hormones ecdysteroid and PTTH
is an example of
A) an interaction of the endocrine and nervous
systems.
B) homeostasis achieved by positive feedback.
C)
how peptide-derived hormones have more widespread effects than steroid
hormones.
D) homeostasis maintained by antagonistic hormones.
E) competitive inhibition of a hormone receptor.
Answer: A