which gland produces hormones that regulate sleep

HESI A2

HESI A2 Practice Test Anatomy and Physiology

1. Which gland produces hormones that regulate sleep?

A. Thyroid gland
B. Pineal gland
C. Adrenal gland
D. Pituitary gland

Correct answer: B

Rationale: The pineal gland secretes melatonin, a hormone that plays a crucial role in regulating the sleep-wake cycle. Melatonin production is influenced by exposure to light, with levels increasing in the evening to promote sleep and decreasing in the morning to signal wakefulness. Choices A, C, and D are incorrect because the thyroid gland primarily regulates metabolism, the adrenal gland produces hormones like adrenaline and cortisol related to stress response, and the pituitary gland controls various functions by releasing different hormones but not specifically related to regulating sleep.

2. What is the role of the gallbladder in digestion?

A. To produce bile
B. To store and concentrate bile
C. To break down fats
D. To secrete digestive enzymes

Correct answer: B

Rationale: The gallbladder's primary function in digestion is to store and concentrate bile produced by the liver. Bile is essential for the digestion and absorption of fats in the small intestine. While the gallbladder does not produce bile (Choice A) or secrete digestive enzymes (Choice D), it plays a crucial role in storing and releasing bile when needed. Therefore, the correct answer is B.

3. The vena cavae drain blood from the body into the ___________.

A. right atrium
B. right ventricle
C. left atrium
D. left ventricle

Correct answer: A

Rationale: The vena cavae are large veins responsible for returning deoxygenated blood from the body to the heart. They empty into the right atrium of the heart. From the right atrium, the blood is then pumped into the right ventricle before being sent to the pulmonary circulation for oxygenation, making choice A, 'right atrium,' the correct answer. Choices B, C, and D are incorrect because the vena cavae do not empty into the ventricles of the heart; instead, they deliver blood to the atria.

4. Which organelle in the cell is responsible for packaging and distributing proteins?

A. Ribosome
B. Golgi apparatus
C. Endoplasmic reticulum
D. Mitochondrion

Correct answer: B

Rationale: The Golgi apparatus is an organelle responsible for packaging and distributing proteins and lipids within the cell. It modifies, sorts, and packages these molecules into vesicles for transportation to their final destinations, either within the cell or outside of it. The Golgi apparatus plays a crucial role in the secretory pathway of cells, ensuring that proteins are properly processed and directed to where they are needed. Ribosomes are responsible for protein synthesis, not packaging and distributing proteins. The endoplasmic reticulum is involved in protein synthesis and folding but not primarily in packaging and distributing proteins. Mitochondria are known as the powerhouse of the cell and are responsible for generating energy in the form of ATP through cellular respiration, not packaging and distributing proteins.

5. What is the function of the medulla oblongata in the brain?

A. To control breathing and heart rate
B. To regulate body temperature
C. To coordinate voluntary movements
D. To process sensory information

Correct answer: A

Rationale: The correct answer is A: To control breathing and heart rate. The medulla oblongata is a vital part of the brainstem responsible for regulating essential functions such as breathing, heart rate, and blood pressure. These functions are crucial for maintaining life, and the medulla oblongata plays a key role in ensuring the body's survival. Choices B, C, and D are incorrect because regulating body temperature is primarily controlled by the hypothalamus, coordinating voluntary movements is associated with the cerebellum and motor cortex, and processing sensory information is related to the thalamus and sensory cortex, not the medulla oblongata.