Question 1

Which of the following statements best explains why water-soluble vitamins must be consumed regularly in the diet?

Accepted Answer

They are not generally stored in the body and excess amounts are excreted in urine.

Question 2

A patient presents with loss of appetite, confusion, muscle weakness, and peripheral neuropathy. Which vitamin deficiency is most likely responsible for these symptoms?

Accepted Answer

Thiamin (Vitamin B\_1)

Question 3

Which metabolic pathway is directly impaired in a person with a thiamin deficiency, leading to decreased ATP production from carbohydrates?

Accepted Answer

Conversion of pyruvate to acetyl CoA

Question 4

A diet high in raw egg whites can lead to a deficiency in which vitamin, and what is the mechanism?

Accepted Answer

Biotin; avidin binds to biotin and prevents absorption

Question 5

Which of the following is a primary function of vitamin C in the human body?

Accepted Answer

Promotes collagen synthesis and acts as an antioxidant

Question 6

A person following a strict vegan diet is at increased risk for which vitamin deficiency, and why?

Accepted Answer

Vitamin B\_12, because it is only found naturally in animal products

Question 7

Which vitamin deficiency is associated with the development of macrocytic anemia and neural tube defects in infants?

Accepted Answer

Folate

Question 8

A patient taking high-dose vitamin B\_6 supplements develops nerve damage and tingling in the legs and feet. What is the most likely explanation?

Accepted Answer

Vitamin B\_6 can accumulate in tissues and reach toxic levels when taken in excess.

Question 9

Which of the following best describes the relationship between folate and vitamin B\_12 in red blood cell synthesis?

Accepted Answer

Vitamin B\_12 activates folate, which is required for DNA synthesis and cell division.

Question 10

A patient presents with dermatitis, diarrhea, dementia, and eventually death if untreated. Which vitamin deficiency is most likely responsible?

Accepted Answer

Niacin (Vitamin B\_3)

Question 11

Which water-soluble vitamin is most likely to be destroyed by exposure to heat and light, and is therefore higher in raw foods than cooked foods?

Accepted Answer

Folate

Question 12

Which of the following is a unique property of riboflavin compared to other water-soluble vitamins?

Accepted Answer

It is destroyed by ultraviolet light but stable during cooking.

Question 13

A patient with chronic alcohol abuse develops confusion, muscle weakness, and heart problems. Which syndrome and vitamin deficiency are most likely present?

Accepted Answer

Wernicke-Korsakoff syndrome; thiamin deficiency

Question 14

Which vitamin acts as a coenzyme in the synthesis of fatty acids, glycogen, and is important for healthy hair and nails?

Accepted Answer

Biotin

Question 15

Which of the following is a symptom of vitamin C deficiency?

Accepted Answer

Scurvy, including bleeding gums and poor wound healing

Question 16

Which vitamin is required for the conversion of pyruvate to acetyl CoA, and what is the relevant coenzyme?

Accepted Answer

Thiamin; thiamin pyrophosphate (TPP)

Question 17

A patient with a sore tongue, depression, and microcytic hypochromic anemia is most likely deficient in which vitamin?

Accepted Answer

Vitamin B\_6

Question 18

Which water-soluble vitamin is essential for the synthesis of acetylcholine, steroid hormones, and cholesterol?

Accepted Answer

Pantothenic acid

Question 19

Which vitamin enhances the absorption of nonheme iron from plant sources?

Accepted Answer

Vitamin C

Question 20

A patient presents with inflamed tissues lining the throat, mouth, tongue, and lips, as well as sore throat and cheilosis. Which vitamin deficiency is most likely?

Accepted Answer

Riboflavin (Vitamin B\_2)

Water-Soluble Vitamins: Structure, Function, and Clinical Relevance

Guida di studio - Domande di pratica

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