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. What is the function of the coronary artery?

A. It carries oxygenated blood to the heart muscle.
B. It carries deoxygenated blood to the lungs.
C. It distributes blood to the body.
D. It supplies blood to the heart muscle.

Correct answer: D

Rationale: The correct answer is D: 'It supplies blood to the heart muscle.' The coronary artery's main function is to supply oxygenated blood to the heart muscle, ensuring that the heart receives the necessary nutrients and oxygen it needs to function properly. Choices A, B, and C are incorrect because the coronary artery specifically delivers oxygenated blood to the heart muscle, not deoxygenated blood to the lungs or blood to the rest of the body.

3. Which organ is responsible for the production of hormones during stress?

A. Parathyroid gland
B. Adrenal cortex
C. Posterior pituitary gland
D. Hypothalamus

Correct answer: B

Rationale: The adrenal cortex is the organ responsible for producing stress hormones like cortisol and aldosterone, which play a crucial role in the body's stress response. During stress, the adrenal cortex releases cortisol, a hormone that helps the body deal with stress by increasing blood sugar, suppressing the immune system, and aiding in metabolism. Parathyroid gland is responsible for calcium regulation, the posterior pituitary gland secretes hormones like oxytocin and vasopressin which are not directly related to the stress response, and the hypothalamus plays a role in regulating hormonal balance and various bodily functions but is not primarily responsible for producing stress hormones.

4. What role does the liver play in metabolism?

A. To produce bile
B. To detoxify harmful substances
C. To store glucose
D. To produce insulin

Correct answer: B

Rationale: The correct answer is B: 'To detoxify harmful substances.' The liver is primarily responsible for detoxifying harmful substances present in the blood as part of its role in metabolism. While the liver does produce bile to aid in digestion and stores glucose for energy regulation, its main function in metabolism is detoxification. The liver does not produce insulin; insulin is produced by the pancreas to regulate blood sugar levels.

5. What is the primary function of the small intestine in digestion?

A. Breaking down fats
B. Absorbing nutrients
C. Secreting digestive enzymes
D. Storing bile

Correct answer: B

Rationale: The correct answer is B: Absorbing nutrients. The small intestine plays a crucial role in digestion by absorbing nutrients. It is where the majority of nutrient absorption occurs, allowing digested food to pass into the bloodstream for distribution to the body's cells. Choice A (Breaking down fats) is incorrect because the breakdown of fats primarily occurs in the small intestine with the help of bile from the liver and enzymes from the pancreas. Choice C (Secreting digestive enzymes) is incorrect because while the small intestine does produce some digestive enzymes, its primary role is absorption. Choice D (Storing bile) is incorrect as the storage of bile occurs in the gallbladder, not the small intestine.