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What is Intrinsic factor is required for absorption of - and explain in detail?
Ans. is 'b' i.e., Vitamin B12 o Vitamin B12 (cyanocobalamine) is absorbed in the ileum, o Intrinsic factor (of castle) is necessary for its absorption. o IF is secreted by oxyntic cells of stomach. In the lumen of the small intestine, IF forms a complex with vitamin B12. o Vitamin B12-IF complex binds with a specific receptor on the surface of the epithelial cells of the ileum. o Vitamin B12 is transported into the enterocytes leaving behing IF at the brush border.