which part of the brain controls voluntary movement

HESI A2

Anatomy HESI A2 Practice Test

1. Which part of the brain controls voluntary movement?

A. Cerebellum
B. Cerebrum
C. Brainstem
D. Medulla oblongata

Correct answer: B

Rationale: The cerebrum, specifically the motor cortex located within it, is responsible for controlling voluntary movements such as walking, writing, and speaking. This region of the brain plays a crucial role in coordinating and executing voluntary muscle actions, making it the correct answer in this context. The cerebellum (Choice A) primarily coordinates balance, posture, and coordination of voluntary movements but does not control voluntary movement itself. The brainstem (Choice C) is responsible for basic life functions like breathing and heart rate, not voluntary movements. The medulla oblongata (Choice D) controls vital functions like blood pressure and breathing, not voluntary movement.

2. Which might be a result of stenosis, or narrowing of a heart valve?

A. Abdominal pain
B. Blood clots
C. Edema (swelling) in organs
D. Irregular heartbeat

Correct answer: D

Rationale: Stenosis, or narrowing of a heart valve, restricts blood flow through the valve, leading to changes in the heart's normal rhythm. This alteration can result in an irregular heartbeat, making it a common consequence of heart valve stenosis. Abdominal pain, blood clots, and organ swelling are not typically associated with stenosis of a heart valve.

3. Which vitamin is essential for vision and skin health?

A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin E

Correct answer: A

Rationale: Vitamin A is the correct answer. It is crucial for maintaining healthy vision and skin. Vitamin A plays a vital role in supporting normal vision, skin health, and immune function. Specifically, it is important for the health of the retina and is essential for the formation of rhodopsin, a protein in the retina necessary for low-light and color vision. Vitamin C (Choice B) is important for collagen synthesis and immune function, but it is not primarily associated with vision health. Vitamin D (Choice C) is crucial for bone health and immune function, while Vitamin E (Choice D) acts as an antioxidant, protecting cells from damage, but neither are primarily linked to vision and skin health like Vitamin A.

4. What is the primary function of the adrenal glands?

A. To produce insulin
B. To regulate metabolism and stress response
C. To fight infections
D. To regulate blood pressure

Correct answer: B

Rationale: The primary function of the adrenal glands is to regulate metabolism and the body's stress response. The adrenal glands produce hormones like cortisol and adrenaline that play a vital role in managing metabolism, immune response, and stress levels. Choice A is incorrect because insulin is produced by the pancreas, not the adrenal glands. Choice C is incorrect because fighting infections is primarily the role of the immune system. Choice D is incorrect as the regulation of blood pressure involves organs like the heart, kidneys, and blood vessels, not the adrenal glands.

5. Which type of blood cell is responsible for carrying oxygen?

A. Red blood cells
B. White blood cells
C. Platelets
D. Plasma cells

Correct answer: A

Rationale: The correct answer is A: Red blood cells. Red blood cells, also known as erythrocytes, are specialized cells designed to transport oxygen from the lungs to tissues and organs throughout the body. These cells contain hemoglobin, a protein that binds to oxygen molecules in the lungs and releases them in other parts of the body where oxygen is needed for cellular respiration. White blood cells (choice B) are part of the immune system, responsible for fighting infections. Platelets (choice C) are involved in blood clotting. Plasma cells (choice D) are a type of white blood cell that produces antibodies to help the body fight off infections.