which part of the brain is responsible for regulating involuntary functions such as breathing and heart rate

HESI A2

Anatomy HESI A2

1. Which part of the brain is responsible for regulating involuntary functions such as breathing and heart rate?

A. Cerebrum
B. Cerebellum
C. Medulla oblongata
D. Frontal lobe

Correct answer: C

Rationale: The medulla oblongata, located in the brain stem, is responsible for regulating involuntary functions such as breathing and heart rate. It contains vital centers that control these essential functions to maintain life. The cerebrum is primarily involved in higher brain functions like thinking and voluntary movements; the cerebellum plays a crucial role in coordinating movement and balance; and the frontal lobe is responsible for functions such as decision-making, problem-solving, and voluntary muscle movements. Therefore, the correct answer is the medulla oblongata (Choice C).

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. What is the primary function of the cardiovascular system?

A. To pump blood throughout the body
B. To deliver nutrients to tissues
C. To regulate body temperature
D. To protect the body from infection

Correct answer: A

Rationale: The primary function of the cardiovascular system is to pump blood throughout the body, ensuring that oxygen and nutrients are delivered to tissues while removing waste products. This circulation is essential for maintaining overall health and proper functioning of the body's cells and organs. Choices B, C, and D are incorrect because while the cardiovascular system does deliver nutrients to tissues indirectly by transporting them in the blood, regulating body temperature is primarily the role of the endocrine and nervous systems, and protecting the body from infection is the main function of the immune system.

4. 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.

5. Which organ system is primarily responsible for integrating voluntary movements?

A. Cardiovascular system
B. Digestive system
C. Respiratory system
D. Nervous system

Correct answer: D

Rationale: The correct answer is D: Nervous system. The nervous system is primarily responsible for integrating voluntary movements. This system includes the brain, spinal cord, and peripheral nerves that communicate signals throughout the body to control movement. The brain interprets sensory information, formulates decisions, and sends signals to the muscles to execute voluntary movements. The cardiovascular system is responsible for circulating blood, the digestive system for breaking down food and absorbing nutrients, and the respiratory system for gas exchange in the body. Choices A, B, and C are incorrect as they do not play a primary role in integrating voluntary movements.