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. The spleen is part of which system?

A. nervous system
B. integumentary system
C. lymphatic system
D. urinary system

Correct answer: C

Rationale: The correct answer is C: lymphatic system. The spleen is a vital organ in the lymphatic system, responsible for filtering blood, producing and storing white blood cells, and aiding the body in fighting infections. The lymphatic system is crucial for maintaining the body's immune defenses and fluid balance. Choices A, B, and D are incorrect because the spleen is not part of the nervous system, integumentary system, or urinary system.

3. What is the most visible part of the ear?

A. Ear canal
B. Cochlea
C. Organ of Corti
D. Pinna

Correct answer: D

Rationale: The pinna, also known as the auricle, is the most visible part of the ear. Its external shape and location make it easily noticeable on the side of the head. The pinna helps in capturing sound waves and directing them into the ear canal, where the sound transmission process begins. The other structures listed, the Organ of Corti, Cochlea, and Ear canal, are essential parts of the ear involved in hearing and sound processing, but they are not as visibly prominent as the pinna. Therefore, the correct answer is the pinna because of its external visibility and role in capturing sound waves.

4. Which of the following are considered normal values for the measure of a person’s pulse and blood pressure?

A. 55 beats per minute and 75 over 60 mm Hg
B. 72 beats per minute and 120 over 80 mm Hg
C. 100 beats per minute and 140 over 100 mm Hg
D. 160 beats per minute and 100 over 70 mm Hg

Correct answer: B

Rationale: Normal values for pulse rate typically range between 60 to 100 beats per minute, while normal blood pressure values are usually around 120/80 mm Hg. Option B falls within these normal ranges for both pulse rate and blood pressure, making it the correct choice. Choices A, C, and D have either pulse rate, blood pressure, or both values outside the normal ranges, making them incorrect.

5. Which vitamin is essential for immune system function?

A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin K

Correct answer: C

Rationale: Vitamin D is the correct answer. It is essential for immune system function as it helps regulate and support the immune response. Vitamin D plays a crucial role in calcium absorption, which is necessary for maintaining strong and healthy bones. Vitamin A is important for vision and skin health, not specifically immune function. Vitamin C is known for its antioxidant properties and its role in collagen production, not primarily for immune system function. Vitamin K is essential for blood clotting and bone health, but it is not directly related to immune system function.