HESI A2
HESI A2 Anatomy and Physiology 2023
1. Which gland is known as the 'master gland' of the body?
- A. Thyroid gland
- B. Adrenal gland
- C. Pituitary gland
- D. Pineal gland
Correct answer: C
Rationale: The pituitary gland, often referred to as the 'master gland,' controls the release of hormones from other endocrine glands in the body. It secretes various hormones that regulate many bodily functions, making it a central and vital component of the endocrine system. The thyroid gland (Choice A) regulates metabolism, the adrenal gland (Choice B) produces hormones like adrenaline, and the pineal gland (Choice D) secretes melatonin, but none of these glands are considered the 'master gland' that controls the functions of other endocrine glands.
2. Which hormone regulates the sleep-wake cycle?
- A. Melatonin
- B. Insulin
- C. Cortisol
- D. Thyroxine
Correct answer: A
Rationale: Melatonin, produced by the pineal gland, is the hormone that regulates the sleep-wake cycle. Its secretion is influenced by light exposure, with levels typically rising in the evening to promote sleep and falling in the morning to encourage wakefulness. Insulin is involved in regulating blood sugar levels, not the sleep-wake cycle. Cortisol plays a role in the body's stress response and circadian rhythm but is not the primary hormone regulating sleep-wake cycles. Thyroxine is a hormone produced by the thyroid gland that regulates metabolism, not the sleep-wake cycle.
3. Which type of blood vessel carries oxygenated blood away from the heart?
- A. Veins
- B. Arteries
- C. Capillaries
- D. Lymphatic vessels
Correct answer: B
Rationale: Arteries are blood vessels that carry oxygenated blood away from the heart to supply tissues and organs with oxygen and nutrients. Veins carry deoxygenated blood back to the heart. Capillaries facilitate the exchange of nutrients and gases between the blood and tissues. Lymphatic vessels are part of the lymphatic system responsible for returning interstitial fluid to the bloodstream. Therefore, the correct answer is arteries as they carry oxygenated blood away from the heart.
4. What is the primary function of the heart?
- A. To filter blood
- B. To transport oxygen and nutrients
- C. To remove waste
- D. To regulate temperature
Correct answer: B
Rationale: The primary function of the heart is to pump oxygenated blood and nutrients throughout the body, supplying cells with vital substances. Choice A is incorrect as the kidneys are responsible for filtering blood. Choice C is incorrect as waste removal is primarily handled by organs like the kidneys and liver. Choice D is incorrect as regulating body temperature is mainly controlled by mechanisms such as sweating and shivering, not the heart.
5. Which vitamin is essential for vision and skin health?
- A. Vitamin A
- B. Vitamin C
- C. Vitamin D
- D. Vitamin E
Correct answer: A
Rationale: Vitamin A is the correct answer. It is crucial for maintaining healthy vision and skin. Vitamin A plays a vital role in supporting normal vision, skin health, and immune function. Specifically, it is important for the health of the retina and is essential for the formation of rhodopsin, a protein in the retina necessary for low-light and color vision. Vitamin C (Choice B) is important for collagen synthesis and immune function, but it is not primarily associated with vision health. Vitamin D (Choice C) is crucial for bone health and immune function, while Vitamin E (Choice D) acts as an antioxidant, protecting cells from damage, but neither are primarily linked to vision and skin health like Vitamin A.
Similar Questions
Access More Features
HESI A2 Basic
$99/ 30 days
- 3,000 Questions with answers
- 30 days access
HESI A2 Premium
$149.99/ 90 days
- Actual HESI A2 Questions
- 3,000 questions with answers
- 90 days access