Question 1

Which of the following best describes the difference between endocrine and exocrine glands?

Accepted Answer

Endocrine glands secrete hormones directly into the bloodstream, while exocrine glands secrete nonhormonal substances onto epithelial surfaces.

Question 2

A patient presents with symptoms of acromegaly. Which hormone is most likely being oversecreted, and from which gland?

Accepted Answer

Growth hormone (GH) from the anterior pituitary gland

Question 3

Which of the following is a correct example of a second messenger system used by water-soluble hormones?

Accepted Answer

Cyclic AMP ($cAMP$) signaling pathway

Question 4

A steroid hormone is circulating in the blood. Which of the following is true regarding its transport and action?

Accepted Answer

It is bound to plasma proteins and acts on intracellular receptors to directly activate genes.

Question 5

Which of the following best explains the concept of 'permissiveness' in hormone interactions at target cells?

Accepted Answer

One hormone cannot exert its full effects without another hormone being present.

Question 6

A patient with diabetes insipidus is most likely deficient in which hormone, and what is its primary function?

Accepted Answer

Antidiuretic hormone (ADH); promotes water reabsorption in the kidneys

Question 7

Which of the following mechanisms is responsible for the rapid termination of cyclic AMP ($cAMP$) signaling in target cells?

Accepted Answer

Degradation by the enzyme phosphodiesterase

Question 8

Which of the following is NOT a stimulus for hormone release from endocrine glands?

Accepted Answer

Mechanical stretch of the gland

Question 9

A patient has low blood calcium levels. Which hormone is released to correct this imbalance, and what is its primary action?

Accepted Answer

Parathyroid hormone (PTH); increases blood calcium by stimulating bone resorption

Question 10

Which of the following best describes the role of the hypothalamus in endocrine regulation?

Accepted Answer

It produces releasing and inhibiting hormones that regulate anterior pituitary hormone secretion.

Question 11

Which of the following hormones uses the PIP$_2$-calcium second messenger system?

Accepted Answer

Oxytocin

Question 12

A patient is experiencing symptoms of hyperthyroidism, such as increased metabolic rate and weight loss. Which condition is most likely responsible?

Accepted Answer

Graves' disease

Question 13

Which of the following is a correct statement about hormone half-life?

Accepted Answer

Steroid and thyroid hormones generally have longer half-lives because they are bound to plasma proteins.

Question 14

Which of the following is an example of a hormone acting via direct gene activation?

Accepted Answer

Testosterone binding to an intracellular receptor and initiating transcription of specific genes

Question 15

Which of the following best explains why only certain cells respond to a particular hormone?

Accepted Answer

Only target cells have specific receptors for that hormone.

Question 16

Which of the following is a correct example of a humoral stimulus for hormone release?

Accepted Answer

Low blood calcium levels stimulate parathyroid hormone (PTH) release.

Question 17

Which of the following is true regarding the onset and duration of hormone activity?

Accepted Answer

Hormones can have rapid or delayed onset, and duration depends on whether the hormone is water or lipid soluble.

Question 18

Which of the following is a correct statement about the relationship between the hypothalamus and the posterior pituitary?

Accepted Answer

The posterior pituitary stores and releases hormones produced by neurons in the hypothalamus.

Question 19

Which of the following is a correct example of a neural stimulus for hormone release?

Accepted Answer

Sympathetic nerve fibers stimulate the adrenal medulla to release catecholamines.

Endocrine System: Structure, Function, and Hormonal Regulation

Study Guide - Practice Questions