which vitamin is synthesized in the skin upon exposure to sunlight

ATI TEAS 7

ati teas 7 science

1. Which vitamin is synthesized in the skin upon exposure to sunlight?

A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin E

Correct answer: C

Rationale: Vitamin D is synthesized in the skin upon exposure to sunlight. When the skin is exposed to sunlight, a form of cholesterol in the skin is converted into vitamin D3 (cholecalciferol) through a series of chemical reactions. Vitamin D plays a crucial role in calcium absorption and bone health. Choice A, Vitamin A, is not synthesized in the skin upon exposure to sunlight; it is obtained through dietary sources. Choice B, Vitamin C, is not synthesized in the skin upon exposure to sunlight either. Vitamin C is obtained through dietary sources like fruits and vegetables. Choice D, Vitamin E, is not synthesized in the skin upon exposure to sunlight. Vitamin E is a fat-soluble vitamin that acts as an antioxidant and is obtained through dietary sources like nuts, seeds, and vegetable oils.

2. Which blood type is known as the universal donor?

A. Type A
B. Type B
C. Type AB
D. Type O

Correct answer: D

Rationale: Type O blood is known as the universal donor because it lacks antigens on the surface of red blood cells. This characteristic makes it compatible with all blood types during transfusions. Type A, Type B, and Type AB blood types have specific antigens that can cause adverse reactions if transfused to an incompatible recipient.

3. What is the medical term for a urinary tract infection (UTI)?

A. Nephritis
B. Cystitis
C. Urethritis
D. All of the above

Correct answer: B

Rationale: The medical term specifically used to refer to a urinary tract infection (UTI) that affects the bladder is cystitis. Nephritis refers to inflammation of the kidneys, and urethritis refers to inflammation of the urethra. As such, cystitis is the correct term for a UTI, making choice B the right answer. Choices A, C, and D are incorrect because they refer to different conditions affecting the urinary system.

4. Which structure, located between the pons and the spinal cord, plays a crucial role in coordinating movements, maintaining balance, and posture?

A. Thalamus
B. Medulla oblongata
C. Cerebellum
D. Hypothalamus

Correct answer: C

Rationale: The correct answer is the cerebellum. The cerebellum, located between the pons and the spinal cord, is responsible for coordinating movements, maintaining balance, and posture. The thalamus functions in relaying sensory and motor signals to the cerebral cortex, the medulla oblongata controls vital autonomic functions such as breathing and heart rate, and the hypothalamus regulates various bodily functions like temperature and hunger. Therefore, the cerebellum is the structure that specifically handles coordination, balance, and posture.

5. What is the tough, fibrous connective tissue that attaches muscle to bone?

A. Fascia
B. Perimysium
C. Tendon
D. Ligament

Correct answer: C

Rationale: Tendons are the correct answer as they are the tough, fibrous connective tissues that attach muscle to bone. They play a crucial role in transmitting the forces generated by muscle contraction to the bones, facilitating movement. Fascia surrounds muscles and provides support, perimysium is the connective tissue sheath around muscle fibers, and ligaments connect bone to bone, stabilizing joints, which makes them distinct from tendons.