which vitamin is important for vision

HESI A2

HESI A2 Practice Test Anatomy and Physiology

1. Which vitamin is important for vision?

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

Correct answer: A

Rationale: The correct answer is Vitamin A. Vitamin A is crucial for maintaining healthy vision, particularly in low-light conditions. It plays a key role in the health of the retina and is necessary for the proper functioning of the eye. Deficiency in Vitamin A can lead to night blindness and other vision problems. Vitamin C is important for the immune system and skin health, not specifically for vision. Vitamin D is essential for bone health and overall well-being, but it is not directly related to vision. Vitamin K is important for blood clotting, but it is not specifically linked to vision.

2. Which system does the esophagus belong to?

A. Endocrine system
B. Digestive system
C. Respiratory system
D. Nervous system

Correct answer: B

Rationale: The esophagus is part of the digestive system. It is a muscular tube that connects the mouth to the stomach, allowing the passage of food and liquids from the mouth to the stomach for digestion. The esophagus plays a crucial role in the process of swallowing and digestion, which are essential functions of the digestive system. Choices A, C, and D are incorrect because the esophagus is not associated with the endocrine, respiratory, or nervous systems.

3. Which cellular structure is responsible for producing energy?

A. Nucleus
B. Mitochondria
C. Ribosome
D. Golgi apparatus

Correct answer: B

Rationale: Mitochondria are the organelles responsible for producing energy in the cell through a process called cellular respiration. They are often referred to as the powerhouses of the cell due to their role in generating ATP, the cell's energy currency. The nucleus is not involved in energy production but houses the cell's genetic material. Ribosomes are responsible for protein synthesis, not energy production. The Golgi apparatus is involved in processing and packaging proteins for secretion, not energy production.

4. Which structure in the ear is responsible for balance?

A. Cochlea
B. Semicircular canals
C. Ossicles
D. Eustachian tube

Correct answer: B

Rationale: The semicircular canals in the inner ear are responsible for maintaining balance by detecting changes in head position and movement. These structures contain fluid and hair cells that send signals to the brain regarding the body's orientation in space, helping us stay balanced and navigate our surroundings. The cochlea is responsible for hearing, the ossicles are involved in sound transmission, and the Eustachian tube helps equalize pressure in the middle ear, but they are not directly related to balance.

5. The skull is positioned ________ to the spinal cord.

A. anterior
B. posterior
C. lateral
D. superior

Correct answer: D

Rationale: The correct answer is D. The skull is superior to the spinal cord, meaning it is located above the spinal cord in anatomical position. Superior in anatomy refers to a structure being positioned higher or above another structure in the body. Choices A, B, and C are incorrect because they refer to different directional relationships. Anterior means in front of, posterior means behind, and lateral means to the side. In this case, the relationship between the skull and the spinal cord is based on a superior-inferior orientation.