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A 44-year-old former alcoholic woman presents with worsening fatigue for the past 2 months. She reports no other symptoms, and physical examination is unremarkable. Laboratory studies reveal a hemoglobin level of 8 g/dL and mean corpuscular volume of 110 ?m³. The blood smear shown in the image was obtained as part of her work-up.
Which of the following is the function of the vitamin causing this patient’s condition?
A. Catalyzes ?-carboxylation of glutamic acid residues
B. Hydroxylates prolyl and lysyl residues
C. Increases intestinal calcium and phosphate absorption
D. Makes up the constituents of the visual pigments
E. Transfers single-carbon intermediates
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probably the answer gonna be E. which is Vitamin B9(folate) single-carbon transfer, also most common vit deff, in USA in Alcoholics mostly, causing megaloblastic anemia which is MCV more then 90fL, and hypersegmented PMN cells, and no neurological symptoms.
E
E
E
it is