Question 1

Which of the following best describes the primary difference between the endocrine and nervous systems in terms of their signaling mechanisms?

Accepted Answer

The endocrine system releases hormones into the blood, while the nervous system releases neurotransmitters at synapses.

Question 2

A patient with diabetes mellitus has sustained high blood glucose levels. Which general function of the endocrine system is most directly affected?

Accepted Answer

Maintaining blood composition and volume

Question 3

Which of the following is an example of humoral stimulation of hormone release?

Accepted Answer

The pancreas releases insulin in response to increased blood glucose.

Question 4

Which hormone category is lipid-soluble and requires a carrier protein for transport in the blood?

Accepted Answer

Steroids

Question 5

What is the primary effect of a lipid-soluble hormone binding to its intracellular receptor?

Accepted Answer

Direct stimulation of mRNA synthesis and protein production

Question 6

Which of the following best describes the role of protein kinase enzymes in the signal transduction pathway initiated by water-soluble hormones?

Accepted Answer

They add phosphate groups to other proteins, altering their activity.

Question 7

A cell exposed to chronically high levels of a hormone decreases its number of receptors for that hormone. This process is called:

Accepted Answer

Down-regulation

Question 8

Which of the following is an example of an antagonistic hormone interaction?

Accepted Answer

Insulin lowering blood glucose while glucagon raises it

Question 9

Which hormone is released from the posterior pituitary and functions to decrease urine production and stimulate thirst?

Accepted Answer

Antidiuretic hormone (ADH)

Question 10

A patient has an enlarged thyroid gland due to insufficient dietary iodine. What is this condition called?

Accepted Answer

Goiter

Question 11

Which hormone is produced by the zona fasciculata of the adrenal cortex and is involved in the stress response?

Accepted Answer

Cortisol

Question 12

Which of the following best describes the effect of insulin on its target cells?

Accepted Answer

Stimulates glycogenesis and lipogenesis

Question 13

Which hormone is secreted by the pineal gland and helps regulate circadian rhythms?

Accepted Answer

Melatonin

Question 14

A patient with Addison disease is likely to experience which of the following symptoms?

Accepted Answer

Weight loss, fatigue, and hypotension

Question 15

Which hormone is released in response to low blood calcium and acts to increase blood calcium levels?

Accepted Answer

Parathyroid hormone (PTH)

Question 16

Which of the following best explains why lipid-soluble hormones require carrier proteins in the blood?

Accepted Answer

They do not dissolve readily in the aqueous environment of blood.

Question 17

Which of the following is a direct effect of thyroid hormone (TH) on target tissues?

Accepted Answer

Increased protein synthesis and calorigenic effect

Question 18

A patient is given a drug that blocks adenylate cyclase activity in target cells. Which hormone signaling pathway would be most directly affected?

Accepted Answer

Water-soluble hormone pathway using cAMP as a second messenger

Question 19

Which hormone is released from the heart and acts to lower blood pressure by increasing urine output and dilating blood vessels?

Accepted Answer

Atrial natriuretic peptide (ANP)

Question 20

Which of the following best describes the effect of aging on the endocrine system?

Accepted Answer

Secretory activity of endocrine glands decreases, leading to reduced hormone levels.

Endocrine System: Structure, Function, and Regulation

Study Guide - Practice Questions