Which mechanism best explains the absorption of Vitamin B12 (Cobalamin) in the terminal ileum?
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Correct answer: Chylomicrons for lymphatic export
Vitamin B12 must bind to Intrinsic Factor (produced by gastric parietal cells) to be protected from digestion. This complex is then recognized by specific receptors (cubilin) in the terminal ileum and absorbed via endocytosis.
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