Which vitamin is essential for the maturation of blood cell precursors________________?
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Answer: D. Cyano cobalamine
Explanation
Cyanocobalamin is a crucial cofactor required for DNA synthesis and normal maturation of blood cell precursors. Deficiency of this vitamin impairs nuclear maturation in rapidly dividing erythroid progenitor cells in bone marrow. Megaloblastic anemia develops when red blood cell precursors fail to divide normally due to insufficient vitamin B12. Vitamin B12 is a complex water-soluble vitamin that must be absorbed from dietary animal sources in the gut. Intrinsic factor produced by gastric parietal cells binds vitamin B12 to facilitate its uptake in the ileum. Cellular enzymes require cobalamin derivatives to convert homocysteine to methionine and support DNA replication.
Option A Vitamin A supports vision and epithelial health rather than serving as the primary hematopoietic cofactor. Option B Thiamine is essential for carbohydrate metabolism and neurological function rather than cell maturation. Option C Riboflavin acts as a coenzyme in various oxidation-reduction reactions across cellular metabolism.
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