Q: Which equation correctly represents the conversion of beta-carotene to retinal in the body?

$$\beta\text{-carotene} \rightarrow 2 \times \text{retinal}$$

Question 1

Which of the following statements best describes the absorption of beta-carotene compared to preformed vitamin A?

Accepted Answer

Beta-carotene is absorbed by passive diffusion, while preformed vitamin A is absorbed by active transport with bile salts and micelles.

Question 2

A strict vegan is concerned about meeting their vitamin A needs. Which dietary strategy would be most effective?

Accepted Answer

Eating foods rich in carotenoids and beta-carotene, such as carrots and sweet potatoes.

Question 3

Which metabolic function is shared by both vitamin D and vitamin K?

Accepted Answer

Promotion of strong bones.

Question 4

A patient presents with bowed legs and bone pain. Laboratory tests reveal low serum calcium and phosphorus. Which vitamin deficiency is most likely responsible?

Accepted Answer

Vitamin D

Question 5

Which of the following is a consequence of excessive intake of preformed vitamin A, but NOT of carotenoids from food?

Accepted Answer

Liver damage and birth defects

Question 6

Which equation correctly represents the conversion of beta-carotene to retinal in the body?

Accepted Answer

$$\beta	ext{-carotene} ightarrow 2 	imes 	ext{retinal}$$

Question 7

Which of the following vitamins acts as a powerful antioxidant and helps prevent oxidation of LDL cholesterol?

Accepted Answer

Vitamin E

Question 8

A newborn infant is at risk for a deficiency in which vitamin, potentially leading to problems with blood clotting?

Accepted Answer

Vitamin K

Question 9

Which of the following statements about vitamin supplementation is TRUE?

Accepted Answer

Supplements can cause adverse side effects and are not a substitute for healthy eating.

Question 10

Which vitamin is considered a prohormone and can be synthesized in the skin upon exposure to sunlight?

Accepted Answer

Vitamin D

Question 11

A patient taking anticoagulant medication is advised to keep their intake of which vitamin consistent to avoid altering drug effectiveness?

Accepted Answer

Vitamin K

Question 12

Which of the following is NOT a function of vitamin A?

Accepted Answer

Blood clotting

Question 13

Which population group may benefit from vitamin B12 supplementation due to decreased absorption with age?

Accepted Answer

Older individuals

Question 14

Which vitamin is involved in the carboxylation of proteins such as osteocalcin, essential for bone matrix formation?

Accepted Answer

Vitamin K

Question 15

A patient presents with muscle weakness and nerve problems. Chronic deficiency of which vitamin is most likely responsible?

Accepted Answer

Vitamin E

Question 16

Which of the following is a recommended daily intake for vitamin D in adults according to the study materials?

Accepted Answer

$$15\ \mu g$$ per day

Question 17

Which vitamin deficiency is the leading cause of preventable blindness in children in developing countries?

Accepted Answer

Vitamin A

Question 18

Which of the following is TRUE regarding vitamin E toxicity?

Accepted Answer

Overconsumption of synthetic vitamin E supplements can increase risk of hemorrhage.

Question 19

Which vitamin is incorporated into chylomicrons and transported via the lymphatic system after absorption?

Accepted Answer

Vitamin E

Question 20

Which of the following is a provitamin and an antioxidant found in plant foods?

Accepted Answer

Beta-carotene

Fat-Soluble Vitamins: Functions, Sources, and Health Implications

Guida di studio - Domande di pratica

Study guide - Flashcard