Vitamins and Coenzymes — Flashcards

Flashcard 41: _____ converts 25-hydroxyvitamin D (calcidiol) into 1,25-dihydroxyvitamin D (aka calcitriol).

Answer: 1-alpha-hydroxylase

Flashcard 42: Vitamin A is found in _____ and leafy vegetables

Answer: liver

Flashcard 43: Vitamin C is found in _____ and vegetables

Answer: fruits

Flashcard 44: Niacin (Vitamin B3) _____ serum triglycerides by decreasing hepatic VLDL secretion

Answer: decreases

Extra: Niacin (Vitamin B3) decreases triglyceride levels by: 1. Inhibiting **hormone-sensitive lipase** in adipose tissue, which reduces the release of free fatty acids (FFA) to the liver. 2. Directly inhibiting hepatic **VLDL synthesis and secretion**. It also increases HDL levels (most potent agent for this) and decreases LDL levels.

Flashcard 45: Vitamin _____ prevents squamous metaplasia

Answer: A

Flashcard 46: Vitamin B2 (riboflavin) is a precursor to _____ and FMN

Answer: FAD

Flashcard 47: Vitamin B12 (cobalamin) is a cofactor for _____ and methylmalonyl-CoA mutase

Answer: methionine synthase

Flashcard 48: Nutritional status of _____ can be assessed by measuring the activity of the RBC glutathione reductase

Answer: riboflavin

Flashcard 49: Vitamin _____ deficiency is characterized by cheilosis and corneal vascularization

Answer: B2

Flashcard 50: _____ excretion test has been used in diagnosing the deficiency of folic acid.

Answer: FIGLU