Vitamins and Nutrition USMLE Step 1 Practice Question
A 23-year-old, single, unemployed female in her eighth month of pregnancy is seen in a volunteer-staffed obstetrics clinic. Her first child, born at home and exclusively breast-fed, had prolonged diarrhea and died from an intracranial hemorrhage at 1 month of age. To help prevent a similar problem in this pregnancy, the resident gives her a free prescription for a vitamin and advises her to take one 20-mg tablet each day. He also informs her that the infant should receive an injection of this vitamin soon after birth. The vitamin prescribed is most likely to be required as a coenzyme in which of the following enzymes?
Answer choices
- AHomocysteine methyltransferase
- Bγ-Glutamyl carboxylaseCorrect answer
- Cδ-Aminolevulinate synthase
- DGlutamic acid decarboxylase
- EProlyl hydroxylase
- FMethionine synthase
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