which organ system is primarily responsible for maintaining temperature control

HESI A2

HESI A2 Anatomy and Physiology Practice Exam

1. Which organ system is primarily responsible for maintaining temperature control?

A. The skeletal system
B. The digestive system
C. The nervous system
D. The integumentary system

Correct answer: D

Rationale: The integumentary system, which includes the skin, hair, and nails, is primarily responsible for maintaining temperature control in the body. The skin helps regulate body temperature through processes like sweating to cool down and shivering to generate heat. Additionally, blood vessels in the skin can dilate or constrict to control the amount of heat lost or retained by the body. This system plays a crucial role in maintaining homeostasis and keeping the body at a stable temperature. The skeletal system (Choice A) provides structural support and protection to the body but is not directly involved in temperature regulation. The digestive system (Choice B) is responsible for breaking down food and absorbing nutrients, not for regulating body temperature. The nervous system (Choice C) controls body functions through electrical impulses but is not the primary system responsible for temperature control.

2. Which parts of the heart are separated by the mitral valve?

A. Left atrium and right atrium
B. Right atrium and right ventricle
C. Left ventricle and right ventricle
D. Left atrium and left ventricle

Correct answer: D

Rationale: The mitral valve, also known as the bicuspid valve, separates the left atrium and the left ventricle of the heart. Its primary function is to prevent the backflow of blood from the left ventricle to the left atrium during the heart's contraction. Therefore, option D, 'Left atrium and left ventricle,' is the correct answer. Choices A, B, and C are incorrect because they do not represent the parts separated by the mitral valve.

3. Which vitamin is essential for the formation of red blood cells?

A. Vitamin A
B. Vitamin B12
C. Vitamin C
D. Vitamin D

Correct answer: B

Rationale: Vitamin B12 is the correct answer. It is crucial for the formation and maturation of red blood cells, playing a vital role in preventing megaloblastic anemia. Additionally, Vitamin B12 is essential for maintaining nerve function. Vitamin A is important for vision and immune function, Vitamin C is necessary for collagen synthesis and immune health, and Vitamin D is crucial for bone health and immune function. Therefore, options A, C, and D are incorrect as they do not play a direct role in the formation of red blood cells.

4. Which organ in the body is responsible for insulin production?

A. Pancreas
B. Liver
C. Gallbladder
D. Kidneys

Correct answer: A

Rationale: The correct answer is the pancreas. The pancreas is responsible for producing insulin, a hormone crucial for regulating blood glucose levels. Insulin plays a key role in allowing cells to take in glucose, thereby helping to keep blood sugar levels in check. The liver (choice B), gallbladder (choice C), and kidneys (choice D) do not produce insulin. The liver is involved in glycogen storage and glucose regulation, the gallbladder stores bile, and the kidneys filter blood and regulate fluid balance.

5. What is the primary role of the liver in the body?

A. Producing insulin
B. Detoxifying harmful substances
C. Digesting food
D. Storing energy

Correct answer: B

Rationale: The correct answer is B: Detoxifying harmful substances. While the liver does produce bile for digestion and stores nutrients like glycogen, its primary function is to filter and detoxify blood coming from the digestive tract before passing it to the rest of the body. Therefore, choices A, C, and D are incorrect. Producing insulin is mainly done by the pancreas, digesting food is primarily the role of the stomach and intestines, and storing energy is a function of various organs like muscles and fat cells.