Hormones and the Endocrine System

Question 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 1

C) Are carried to target cells in the blood

Question 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 2

A) an increase in A always produces an increase in X.

Question 3

which of below options is responsible for Bicarbonate production in the body:
A) duodenum
B) salivary glands
C) liver
D) pancreas

Answer 3

D) Pancreas

Question 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 4

A) Neurohormones

Question 5

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 5

B) only its target cells contain aldosterone receptors

Question 6

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 6

A) negative feedback typically regulates hormone secretion.

Question 7

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 7

E) usually operate as part of a negative feedback system.

Question 8

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 8

C) a hormone that is involved in a positive feedback loop.

Question 9

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 9

A) Peptide hormones

Question 10

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 10

C) hypothalamus and anterior pituitary.

Question 11

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 11

E) Kidney

Question 12

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 12

C) is an evolutionarily conserved hormone.

Question 13

) A product of the anterior pituitary gland that causes color changes in its target cells is
A) FSH.
B) LH.
C) TSH.
D) MSH.
E) ACTH.

Answer 13

D) MSH

Question 14

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 14

B) Prolactin and oxytocin

Question 15

Oxytocin and antidiuretic hormone are synthesized in the
A) hypothalamus.
B) adenohypophysis.
C) anterior pituitary.
D) adrenal cortex.
E) posterior pituitary.

Answer 15

A) hypothalamus.

Question 16

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 16

C) Thyroid Glands

Question 17

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 17

A) diabetes insipidus and the posterior pituitary gland

Question 18

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 18

A) an undersecretion of thyroxine.

Question 19

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 19

D) the adrenal medulla, leading to increased secretion of epinephrine.

Question 20

The endocrine glands include the
A) parathyroid glands.
B) salivary glands.
C) sweat glands.
D) sebaceous glands.
E) gallbladder.

Answer 20

A) Parathyroid Glands

Question 21

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 21

D) Calcitonin

Question 22

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 22

D) the pancreas

Question 23

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 23

B) the skeletal muscles and the adipose cells take up glucose at a faster rate.

Question 24

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 24

C) Adrenocoritcotropic hormone (ACTH)

Question 25

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 25

C) ACTH stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal
medulla.

Question 26

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 26

B) Cortisol

Question 27

Role of Antidiuretic hormone (ADH):
A) to decrease the volume of urine produced
B) to increase the amount of water in urine
C) both options are correct
D) none of above

Answer 27

A) to decrease the volume of urine produced

Question 28

After eating a carbohydrate-rich meal, the mammalian pancreas increases its secretion of
A) ecdysone.
B) glucagon.
C) thyroxine.
D) oxytocin.
E) insulin

Answer 28

E) insulin

Question 29

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 29

D) Oxytocin

Question 30

Testosterone is an example of
A) an androgen.
B) an estrogen.
C) a progestin.
D) a catecholamine.
E) an adrenal steroid.

Answer 30

A) An androgen