which organ system is largely responsible for controlling stress

HESI A2

HESI A2 Anatomy and Physiology Practice Exam

1. Which organ system is largely responsible for controlling stress?

A. The endocrine system
B. The digestive system
C. The lymphatic system
D. The respiratory system

Correct answer: A

Rationale: The endocrine system is largely responsible for controlling stress through the release of hormones such as cortisol and adrenaline. These hormones help regulate the body's response to stress by increasing heart rate, blood pressure, and energy production. The endocrine system plays a crucial role in the body's stress response and helps the body adapt to and cope with stressful situations. The digestive system (Choice B) is primarily responsible for breaking down food and absorbing nutrients, not controlling stress. The lymphatic system (Choice C) is responsible for immune function and maintaining fluid balance, not controlling stress. The respiratory system (Choice D) is responsible for the exchange of oxygen and carbon dioxide, not controlling stress.

2. What is the main function of white blood cells?

A. To carry oxygen
B. To fight infections
C. To carry nutrients
D. To remove waste products

Correct answer: B

Rationale: The main function of white blood cells, also known as leukocytes, is to fight infections and foreign invaders to protect the body from harm. They play a crucial role in the immune system by identifying and destroying pathogens like bacteria and viruses, essential for maintaining the body's health and overall immunity. Choices A, C, and D are incorrect as carrying oxygen is primarily done by red blood cells, carrying nutrients is a function of various body systems, and removing waste products is mainly the role of the kidneys and liver, not white blood cells.

3. What does the parathyroid hormone regulate?

A. Magnesium
B. Calcium
C. Calcitonin
D. Glucocorticoids

Correct answer: B

Rationale: The parathyroid hormone primarily regulates calcium levels in the blood. It acts to increase calcium levels by stimulating the release of calcium from bones, enhancing calcium reabsorption in the kidneys, and promoting the conversion of vitamin D to its active form, which aids in calcium absorption from the intestines. Therefore, the correct answer is B. Choices A, C, and D are incorrect because the parathyroid hormone does not play a significant role in the regulation of magnesium (Choice A), calcitonin (Choice C), or glucocorticoids (Choice D).

4. What is the primary function of the hypothalamus?

A. Regulates body balance and thermoregulation
B. Controls hunger and thirst
C. Regulates sleep and circadian rhythms
D. Controls voluntary movements

Correct answer: A

Rationale: The primary function of the hypothalamus is to regulate body balance and thermoregulation. It plays a crucial role in maintaining overall body equilibrium by controlling functions such as body temperature and water balance. While the hypothalamus is also involved in hunger and thirst regulation, its main role is to ensure homeostasis by monitoring and adjusting body balance and temperature. Choices B, C, and D are incorrect because hunger and thirst regulation, sleep and circadian rhythm regulation, and control of voluntary movements are secondary functions of the hypothalamus compared to its primary role in maintaining body balance and thermoregulation.

5. Where will a person who has damage to their ulnar nerve experience decreased sensation?

A. Leg
B. Arm
C. Face
D. Abdomen

Correct answer: B

Rationale: The ulnar nerve innervates the forearm and hand, specifically providing sensation to the ring and little fingers. Damage to this nerve can lead to decreased sensation in these areas, making the arm the correct answer. Choices A, C, and D are incorrect because the ulnar nerve does not supply sensation to the leg, face, or abdomen.