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 hormone is not produced by the pituitary gland?

A. FSH
B. TRH
C. LH
D. ADH

Correct answer: B

Rationale: Thyrotropin-releasing hormone (TRH) is not produced by the pituitary gland. TRH is actually produced by the hypothalamus and acts on the pituitary gland to stimulate the release of thyroid-stimulating hormone (TSH). On the other hand, FSH (follicle-stimulating hormone), LH (luteinizing hormone), and ADH (antidiuretic hormone) are all hormones directly produced by the pituitary gland.

3. Which part of the brain controls involuntary actions such as breathing and heart rate?

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

Correct answer: C

Rationale: The medulla oblongata, located at the base of the brainstem, controls essential involuntary actions such as breathing, heart rate, and blood pressure. It plays a crucial role in maintaining vital functions necessary for survival. The cerebrum is responsible for voluntary actions, conscious thought, and sensory processing, making it an incorrect choice. The cerebellum primarily coordinates movement, balance, and posture, not involuntary actions like breathing and heart rate. The hypothalamus regulates body temperature, thirst, hunger, and controls the endocrine system, but it is not directly responsible for controlling breathing and heart rate.

4. Where does digestion begin in the digestive system?

A. Stomach
B. Mouth
C. Small intestine
D. Esophagus

Correct answer: B

Rationale: Digestion begins in the mouth. Mechanical digestion through chewing and chemical digestion through saliva initiate the breakdown of food. Enzymes in saliva start breaking down carbohydrates, marking the beginning of the digestive process. The stomach primarily functions in further breaking down food and mixing it with gastric juices. The small intestine is where most of the digestion and absorption of nutrients occur. The esophagus is a muscular tube that helps move food from the mouth to the stomach, but digestion does not begin there.

5. The anterior chamber of the eye lies between the ___________.

A. iris and lens
B. lens and retina
C. cornea and iris
D. retina and optic nerve

Correct answer: A

Rationale: The anterior chamber of the eye is the fluid-filled space located between the cornea and the iris in the front part of the eye. It contains aqueous humor and helps maintain intraocular pressure. The space between the iris and the lens is known as the anterior chamber, making option A, 'iris and lens,' the correct choice. Options B, C, and D are incorrect because they do not describe the correct anatomical location of the anterior chamber.