Q: Which of the following equations correctly represents the negative feedback control of thyroid hormone production?

$$TRH \rightarrow TSH \rightarrow T_3$/T_4$ \rightarrow \text{inhibition of TRH and TSH}$$

Question 1

Which of the following best describes a key difference between the endocrine and nervous systems in terms of intercellular communication?

Accepted Answer

The endocrine system releases hormones into the bloodstream, resulting in slower but longer-lasting effects.

Question 2

Which of the following is NOT a major class of hormones based on chemical structure?

Accepted Answer

Carbohydrate hormones

Question 3

A patient presents with symptoms of excessive thirst, frequent urination, and high blood glucose. Which endocrine disorder is most likely, and which hormone is primarily involved?

Accepted Answer

Diabetes mellitus; insulin

Question 4

Which of the following best explains the mechanism of negative feedback in the hypothalamic-pituitary-thyroid axis?

Accepted Answer

High levels of thyroid hormones inhibit the release of TRH and TSH.

Question 5

A tumor in the adrenal cortex causes excessive secretion of cortisol. Which of the following symptoms would most likely be observed?

Accepted Answer

High blood pressure and muscle weakness

Question 6

Which hormone is produced by the pineal gland and what is its primary function?

Accepted Answer

Melatonin; regulation of circadian rhythms

Question 7

A patient has low calcium levels in the blood. Which hormone is most likely to be secreted in response, and by which gland?

Accepted Answer

Parathyroid hormone by the parathyroid glands

Question 8

Which of the following best describes the function of antidiuretic hormone (ADH)?

Accepted Answer

Increases water reabsorption in the kidneys

Question 9

Which of the following equations correctly represents the negative feedback control of thyroid hormone production?

Accepted Answer

$$TRH ightarrow TSH ightarrow T_3$/T_4$ ightarrow 	ext{inhibition of TRH and TSH}$$

Question 10

Which hormone is secreted by the alpha cells of the pancreas, and what is its primary effect?

Accepted Answer

Glucagon; raises blood glucose

Question 11

A patient with a pituitary tumor is experiencing abnormal growth of bones and tissues. Which hormone is most likely being overproduced?

Accepted Answer

Growth hormone (GH)

Question 12

Which of the following best describes the role of the kidneys as an endocrine organ?

Accepted Answer

They secrete erythropoietin, which stimulates red blood cell production.

Question 13

A patient is diagnosed with hypothyroidism. Which of the following laboratory findings would you expect?

Accepted Answer

Low $$T_3$$ and $$T_4$$, high TSH

Question 14

Which of the following is a correct pairing of an endocrine gland and a hormone it produces?

Accepted Answer

Thyroid gland – thyroxine ($$T_4)$$

Question 15

Which hormone is responsible for stimulating the release of milk from the mammary glands during breastfeeding?

Accepted Answer

Oxytocin

Question 16

A patient with Addison's disease is likely to have which of the following symptoms?

Accepted Answer

Hypotension and hyperpigmentation

Question 17

Which of the following best describes the function of luteinizing hormone (LH) in females?

Accepted Answer

Stimulates ovulation and formation of the corpus luteum

Question 18

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

Accepted Answer

Stimulates osteoclast activity to release calcium into the blood

Question 19

Which of the following best explains how hormones can produce coordinated physiological responses in the body?

Accepted Answer

Hormones bind to specific receptors on target cells, triggering signal transduction pathways.

Question 20

A patient is experiencing symptoms of hyperthyroidism, including weight loss, heat intolerance, and increased heart rate. Which hormone is most likely elevated?

Accepted Answer

Thyroxine ($$T_4)$$

Study Notes: The Endocrine System (Chapter 16 Learning Outcomes)

Study Guide - Practice Questions

Study Guide - Flashcards