Parietal cells in the stomach secrete a protein crucial for the absorption of vitamin B12 by the ileum. What is this protein?
Ans. A. Intrinsic factorIntrinsic factor is critical for the absorption of vitamin B12 by the ileum. None of the other substances is secreted by parietal cells. Gastrin, somatostatin, and CCK are secreted by specialized GI endocrine cells, whereas chylomicrons are produced by enterocytes
Intrinsic factor
Gastrin
Somatostatin
Cholecystokinin (CCK)
G.I.T.