Question 1

Which of the following best distinguishes the adrenal cortex from the adrenal medulla?

Accepted Answer

The adrenal cortex produces steroid hormones such as cortisol and aldosterone, while the adrenal medulla produces catecholamines such as epinephrine and norepinephrine.

Question 2

Which hormone is secreted by the zona fasciculata of the adrenal cortex, and what is its primary effect?

Accepted Answer

Cortisol; increases blood glucose through gluconeogenesis.

Question 3

Crossover effects are observed with steroid hormones because:

Accepted Answer

Steroid hormones can activate multiple types of intracellular receptors, leading to effects in different tissues.

Question 4

Which of the following correctly diagrams the HPA (hypothalamic-pituitary-adrenal) pathway for cortisol secretion?

Accepted Answer

$$Hypothalamus \rightarrow CRH \rightarrow Anterior\ Pituitary \rightarrow ACTH \rightarrow Adrenal\ Cortex \rightarrow Cortisol$$

Question 5

Cortisol is considered to have which type of metabolic effect, and what is one of its main actions?

Accepted Answer

Catabolic; stimulates gluconeogenesis in the liver.

Question 6

Exogenous administration of cortisol can lead to which negative feedback effect?

Accepted Answer

Suppression of endogenous CRH and ACTH production.

Question 7

Which of the following is NOT a typical effect of hypercortisolism (Cushing's syndrome)?

Accepted Answer

Hypoglycemia and weight loss.

Question 8

Which hormone is derived from POMC (pro-opiomelanocortin) and what is one of its physiological effects?

Accepted Answer

ACTH; stimulates cortisol production in the adrenal cortex.

Question 9

Which cell type in the thyroid gland secretes calcitonin?

Accepted Answer

Parafollicular (C) cells.

Question 10

Which of the following best describes the process of thyroid hormone synthesis?

Accepted Answer

Iodine is actively transported into follicular cells, incorporated into thyroglobulin, and then released as T3 and T4 after proteolysis.

Question 11

Which is the more biologically active thyroid hormone?

Accepted Answer

T3 (triiodothyronine)

Question 12

What is a primary effect of hyperthyroidism?

Accepted Answer

Increased metabolic rate and heat intolerance.

Question 13

Which hormone stimulates the release of growth hormone (GH) from the anterior pituitary?

Accepted Answer

Growth hormone-releasing hormone (GHRH)

Question 14

Insulin-like growth factors (IGFs) play a major role in:

Accepted Answer

Mediating the growth-promoting effects of growth hormone.

Question 15

Which of the following is a direct effect of parathyroid hormone (PTH) on bone?

Accepted Answer

Stimulates osteoclasts to resorb bone and release calcium.

Question 16

Which process best describes bone resorption?

Accepted Answer

Osteoclasts break down bone matrix, releasing calcium and phosphate into the blood.

Question 17

Where is most of the body's calcium found?

Accepted Answer

In the bones and teeth.

Question 18

Which hormone increases plasma calcium levels by stimulating intestinal absorption and bone resorption?

Accepted Answer

Calcitriol (active vitamin D)

Question 19

Which population is at greatest risk for developing osteoporosis?

Accepted Answer

Postmenopausal women.

Question 20

Which preventative measure is most effective for young women to reduce the risk of osteoporosis later in life?

Accepted Answer

Consuming adequate calcium and vitamin D, and engaging in regular weight-bearing exercise.

Endocrine System: Hormones and Homeostasis – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard