Question 1

Which of the following best describes how the endocrine system maintains homeostasis?

Accepted Answer

By releasing hormones that act as long-distance chemical signals to regulate target organs.

Question 2

Amino acid–based hormones differ from steroid hormones in their mechanism of action. Which statement correctly explains this difference?

Accepted Answer

Amino acid–based hormones bind to membrane receptors and activate second messenger systems, while steroid hormones enter cells and bind to intracellular receptors.

Question 3

Which equation best represents the negative feedback regulation of hormone levels?

Accepted Answer

If $$[H] is $$hormone concentration, then $$\frac{d[H]}{dt} = S - R([H])$$, where $$S is $$secretion rate and $$R([H]) is $$removal rate increasing with $$[H].$$

Question 4

A patient presents with symptoms of hyperthyroidism, including weight loss, rapid heartbeat, and exophthalmos. Which disorder is most likely?

Accepted Answer

Graves' disease

Question 5

Which hormone is released by the posterior pituitary and is responsible for water reabsorption in the kidneys?

Accepted Answer

Antidiuretic hormone (ADH)

Question 6

Which of the following best explains how water-soluble hormones exert their effects?

Accepted Answer

They bind to membrane receptors, activating second messenger systems such as $$cAMP.$$

Question 7

Which hormone is secreted by the adrenal cortex and is primarily responsible for regulating sodium and potassium balance?

Accepted Answer

Aldosterone

Question 8

A patient with low blood calcium is found to have decreased parathyroid hormone (PTH) levels. Which physiological effect would most likely occur?

Accepted Answer

Reduced osteoclast activity, leading to decreased release of calcium from bones.

Question 9

Which of the following is a correct example of hormonal stimulus triggering hormone release?

Accepted Answer

The hypothalamus releases TRH, which stimulates the anterior pituitary to release TSH.

Question 10

Which equation best describes the relationship between insulin and blood glucose levels?

Accepted Answer

If $$[G] is $$blood glucose and $$I is $$insulin, then $$\frac{d[G]}{dt} = -kI[G]$$, where $$k is a $$constant.

Question 11

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

Accepted Answer

Melatonin

Question 12

Which of the following best describes the relationship between the hypothalamus and the pituitary gland?

Accepted Answer

The hypothalamus controls the anterior pituitary via releasing and inhibiting hormones, and the posterior pituitary via neural connections.

Question 13

Which scenario best illustrates the integration of the endocrine and nervous systems?

Accepted Answer

During stress, the hypothalamus activates the sympathetic nervous system and stimulates the adrenal medulla to release epinephrine.

Question 14

Which hormone is responsible for stimulating milk production in the mammary glands?

Accepted Answer

Prolactin (PRL)

Question 15

A patient with Cushing’s syndrome is likely to have which of the following symptoms?

Accepted Answer

Elevated blood glucose, muscle wasting, and fat redistribution.

Question 16

Which of the following best describes the role of thymic hormones?

Accepted Answer

They promote maturation of T lymphocytes for immune function.

Question 17

Which equation best represents the effect of growth hormone (GH) on body growth?

Accepted Answer

If $$G is $$growth rate and $$[GH] is $$growth hormone concentration, then $$G = k 	imes [GH]$$, where $$k is a $$proportionality constant.

Question 18

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

Accepted Answer

Low blood calcium levels stimulate the parathyroid glands to release PTH.

Question 19

Which of the following best explains why steroid hormones have longer-lasting effects than amino acid–based hormones?

Accepted Answer

Steroid hormones are lipid-soluble, bind to intracellular receptors, and alter gene expression, leading to prolonged effects.

Question 20

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

Accepted Answer

Hormonal responsiveness decreases, and some glands (like the thymus) undergo involution.

Chapter 15: The Endocrine System – Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards