Nursing Elites

1. Which hormone is responsible for regulating the sleep-wake cycle?

• A. Melatonin
• B. Thyroxine
• C. Insulin
• D. Cortisol

Correct answer: A

Rationale: Melatonin, produced by the pineal gland, regulates the sleep-wake cycle by responding to light and darkness in the environment. It plays a crucial role in signaling the body when it's time to sleep and wake up, helping to establish and maintain a healthy circadian rhythm. Thyroxine, Insulin, and Cortisol do not directly regulate the sleep-wake cycle, making them incorrect choices for this question.

2. Which of the following structures regulates the transport of substances in and out of a cell?

• A. Nucleus
• B. Cell membrane
• C. Cytoplasm
• D. Mitochondria

Correct answer: B

Rationale: The cell membrane, also known as the plasma membrane, is responsible for regulating the transport of substances in and out of the cell. It acts as a selective barrier, allowing the passage of certain molecules while restricting others. This selective permeability helps maintain homeostasis within the cell by controlling the movement of essential substances like nutrients and waste products. The nucleus (Choice A) is the organelle that houses the cell's genetic material and is not directly involved in regulating substance transport. Cytoplasm (Choice C) is the gel-like substance that fills the cell and does not play a direct role in regulating substance transport. Mitochondria (Choice D) are responsible for energy production in the cell through cellular respiration and are not primarily involved in substance transport.

3. What is the primary function of the cardiovascular system?

• A. To transport oxygen and nutrients
• B. To regulate body temperature
• C. To remove waste products
• D. To produce hormones

Correct answer: A

Rationale: The correct answer is A: 'To transport oxygen and nutrients.' The primary function of the cardiovascular system is to transport oxygen, nutrients, and hormones to cells throughout the body and remove waste products. Choice B is incorrect because regulating body temperature is primarily the function of the body's thermoregulatory system, including sweat glands and blood vessels near the skin surface. Choice C is incorrect because while the cardiovascular system does help remove waste products through circulation, it is not its primary function. Choice D is incorrect as hormone production is mainly carried out by endocrine glands, not the cardiovascular system.

4. Which vitamin is essential for maintaining healthy skin and vision?

• A. Vitamin C
• B. Vitamin A
• C. Vitamin D
• D. Vitamin K

Correct answer: B

Rationale: Vitamin A is the correct answer. It is essential for maintaining healthy skin and vision, especially in low-light conditions. Vitamin A helps in the production of retinal pigments necessary for vision in dim light and supports skin health by promoting cell turnover and repair. Choice A, Vitamin C, is important for the immune system and collagen production but is not specifically known for maintaining skin and vision health. Choice C, Vitamin D, is crucial for bone health and immune function but is not directly related to skin and vision health. Choice D, Vitamin K, is necessary for blood clotting and bone health but does not play a significant role in maintaining healthy skin and vision.

5. Which neurotransmitter controls sleep, mood, and appetite?

• A. Serotonin
• B. Oxytocin
• C. Cortisol
• D. Aldosterone

Correct answer: A

Rationale: Serotonin is the correct answer. It is a neurotransmitter that plays a crucial role in regulating mood, sleep, and appetite. Serotonin functions to stabilize and control these physiological processes in the brain and body. Imbalances in serotonin levels are commonly linked to conditions like depression, anxiety, and eating disorders. Oxytocin (Choice B) is more associated with social bonding and childbirth. Cortisol (Choice C) is a stress hormone, and while it can influence mood and appetite in response to stress, it is not primarily responsible for regulating these functions. Aldosterone (Choice D) is a hormone that regulates electrolyte balance and blood pressure, not mood, sleep, and appetite.

Similar Questions