which organ system is primarily responsible for regulating electrolytes

HESI A2

HESI A2 Anatomy and Physiology Practice Test

1. Which organ system is primarily responsible for regulating electrolytes?

A. The endocrine system
B. The urinary system
C. The lymphatic system
D. The nervous system

Correct answer: B

Rationale: The urinary system, specifically the kidneys, is primarily responsible for regulating electrolytes in the body by filtering and excreting excess electrolytes, such as sodium, potassium, and chloride, through urine. The kidneys play a crucial role in maintaining the body's electrolyte balance, which is essential for various bodily functions and overall health. The endocrine system regulates hormones, the lymphatic system is involved in immunity, and the nervous system controls communication in the body. Therefore, the correct answer is B, the urinary system, as it directly handles electrolyte regulation by adjusting their excretion levels.

2. Which hormone is produced by the pancreas?

A. Insulin
B. Glucagon
C. Somatostatin
D. Cortisol

Correct answer: A

Rationale: Insulin is the correct answer. Insulin is produced by the pancreas and plays a crucial role in regulating blood glucose levels. It facilitates the uptake of glucose into cells, helping to lower blood sugar levels. Glucagon, on the other hand, is also produced by the pancreas but functions to raise blood glucose levels by stimulating the release of glucose from the liver. Somatostatin is another hormone produced by the pancreas that helps regulate the endocrine system. Cortisol, produced by the adrenal glands, plays a role in stress response and metabolism, not by the pancreas.

3. Which organ is involved in the immune system?

A. Heart
B. Bronchi
C. Appendix
D. Esophagus

Correct answer: C

Rationale: The correct answer is the Appendix. The appendix is now known to play a role in the immune system by housing beneficial bacteria that aid in maintaining gut health and supporting immune responses. This organ contributes to overall immune function. Choices A, B, and D are incorrect as the heart, bronchi, and esophagus are not primarily associated with the immune system.

4. Which of the following is not part of the central nervous system?

A. Retina
B. Spinal cord
C. Brain
D. Heart

Correct answer: B

Rationale: The central nervous system consists of the brain and spinal cord, which are responsible for processing and coordinating information. The retina is part of the eye, while the heart is part of the circulatory system. Therefore, the correct answer is 'Spinal cord' as it is not part of the central nervous system.

5. Which gland is often referred to as the 'master gland'?

A. Thyroid gland
B. Pituitary gland
C. Adrenal gland
D. Pineal gland

Correct answer: B

Rationale: The pituitary gland is often referred to as the 'master gland' because it controls the release of hormones from other endocrine glands in the body. It secretes a variety of hormones that regulate various bodily functions and play a crucial role in maintaining homeostasis. The thyroid gland (Choice A) plays a role in regulating metabolism, the adrenal gland (Choice C) secretes hormones involved in stress response, and the pineal gland (Choice D) produces melatonin to regulate sleep-wake cycles, but they are not known as the 'master gland' due to their functions.