which vitamin is essential for vision and skin health

HESI A2

Anatomy HESI A2 Practice Test

1. 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.

2. Which vitamin is essential for the maintenance of healthy skin?

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

Correct answer: A

Rationale: Vitamin A is the correct answer. It is crucial for maintaining healthy skin as it supports skin cell growth, repair, and overall skin health. Additionally, vitamin A plays a role in vision and immune function. Deficiency in vitamin A can lead to skin issues such as dryness and poor wound healing. Vitamin C is known for its role in collagen synthesis and antioxidant properties, while Vitamin D is important for bone health and immunity. Vitamin K is essential for blood clotting, but it is not primarily associated with skin health.

3. If an impulse is traveling from a sense receptor toward the spinal cord, it is traveling along what type of neuron?

A. Motor neuron
B. Sensory neuron
C. Interneuron
D. Bipolar neuron

Correct answer: B

Rationale: The correct answer is B: Sensory neuron. A sensory neuron is responsible for carrying impulses from sensory receptors to the spinal cord. These neurons transmit information about external stimuli from the periphery to the central nervous system for processing and response. Choice A, Motor neuron, is incorrect as motor neurons carry signals from the central nervous system to muscles and glands, enabling movement and secretion. Choice C, Interneuron, is incorrect as interneurons act as connectors between sensory and motor neurons, primarily facilitating communication between the two. Choice D, Bipolar neuron, is incorrect as bipolar neurons are specialized sensory neurons found in some sensory organs like the retina of the eye and the olfactory epithelium.

4. What is the most visible part of the ear?

A. Ear canal
B. Cochlea
C. Organ of Corti
D. Pinna

Correct answer: D

Rationale: The pinna, also known as the auricle, is the most visible part of the ear. Its external shape and location make it easily noticeable on the side of the head. The pinna helps in capturing sound waves and directing them into the ear canal, where the sound transmission process begins. The other structures listed, the Organ of Corti, Cochlea, and Ear canal, are essential parts of the ear involved in hearing and sound processing, but they are not as visibly prominent as the pinna. Therefore, the correct answer is the pinna because of its external visibility and role in capturing sound waves.

5. What is the main function of the skeletal system?

A. To produce red blood cells
B. To protect internal organs and provide support
C. To regulate body temperature
D. To store calcium

Correct answer: B

Rationale: The main function of the skeletal system is to provide structural support, protect internal organs, enable movement, and maintain the body's form. Choice A, 'To produce red blood cells,' is incorrect as the skeletal system's role in blood cell production is through the bone marrow, not its main function. Choice C, 'To regulate body temperature,' is incorrect as the skeletal system is not primarily responsible for regulating body temperature. Choice D, 'To store calcium,' is partially correct as the skeletal system does store calcium but this is not its main function; instead, it is essential for bone strength and muscle function.