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 substances onto body surfaces or into body cavities via ducts.

Question 2

A patient is experiencing low blood calcium levels. Which hormone is most likely to be secreted in response, and what is one of its direct effects?

Accepted Answer

Parathyroid hormone (PTH); stimulates calcium reabsorption in the kidneys.

Question 3

Which of the following is a correct sequence for the hormone cascade pathway regulating thyroid hormone levels?

Accepted Answer

Hypothalamus releases TRH → Anterior pituitary releases TSH → Thyroid gland releases thyroid hormone

Question 4

Which of the following best explains why the same hormone can produce different effects in different target cells?

Accepted Answer

Different target cells have different receptors or signal transduction pathways for the hormone.

Question 5

Which of the following is a water-soluble hormone and what is its typical cellular response pathway?

Accepted Answer

Epinephrine; binds to cell-surface receptors and triggers signal transduction via second messengers.

Question 6

A researcher observes that nitric oxide (NO) is released when blood oxygen levels fall. What is the physiological effect of NO in this scenario?

Accepted Answer

NO activates an enzyme that relaxes smooth muscle cells, increasing blood flow to tissues.

Question 7

Which feedback mechanism is illustrated by the following scenario: The release of milk by a mammal causes greater suckling by offspring, which stimulates the release of more oxytocin?

Accepted Answer

Positive feedback

Question 8

Which equation correctly represents the conversion of ATP to cyclic AMP (cAMP) during epinephrine signaling?

Accepted Answer

$$ATP \xrightarrow{adenylyl\ cyclase} cAMP + PP_i$$

Question 9

Which hormone is secreted by the anterior pituitary and stimulates the liver to release insulin-like growth factors (IGFs)?

Accepted Answer

Growth hormone (GH)

Question 10

A patient has abnormally high levels of cortisol. Which gland is most likely overactive, and what is one effect of excess cortisol?

Accepted Answer

Adrenal cortex; suppression of the immune system.

Question 11

Which of the following is a correct description of paracrine signaling?

Accepted Answer

The target cells lie near the secreting cells and are reached by diffusion of local regulators.

Question 12

Which hormone is primarily responsible for preparing and maintaining the uterus in mammals?

Accepted Answer

Progesterone

Question 13

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

Accepted Answer

It coordinates endocrine signaling by receiving nervous input and initiating neuroendocrine signals.

Question 14

Which hormone is secreted by the posterior pituitary and regulates water balance in the body?

Accepted Answer

Antidiuretic hormone (ADH)

Question 15

Which of the following is a correct statement about steroid hormones?

Accepted Answer

They are lipid-soluble and bind to receptors in the cytoplasm or nucleus.

Question 16

Which hormone is secreted by the pineal gland and is involved in regulating biological rhythms?

Accepted Answer

Melatonin

Question 17

Which of the following is a direct effect of epinephrine during the 'fight-or-flight' response?

Accepted Answer

Increase in glycogen breakdown and release of glucose into the blood.

Question 18

Which equation best represents the negative feedback loop in secretin signaling?

Accepted Answer

$$	ext{Low pH} ightarrow 	ext{Secretin release} ightarrow 	ext{Bicarbonate release} ightarrow 	ext{Increase pH} ightarrow 	ext{Inhibition of secretin release}$$

Question 19

Which of the following is a correct description of autocrine signaling?

Accepted Answer

The target cell is also the secreting cell.

Hormones and the Endocrine System: Chapter 45 Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards