<P> Intrinsic factor ( IF ) , also known as gastric intrinsic factor ( GIF ) , is a glycoprotein produced by the parietal cells of the stomach . It is necessary for the absorption of vitamin B12 later on in the ileum of the small intestine . In humans , the gastric intrinsic factor protein is encoded by the GIF gene . </P>
<P> Intrinsic factor ( IF ) , also known as gastric intrinsic factor ( GIF ) , is a glycoprotein produced by the parietal cells of the stomach . It is necessary for the absorption of vitamin B12 later on in the ileum of the small intestine . In humans , the gastric intrinsic factor protein is encoded by the GIF gene . </P>
where is b12 absorbed in the gi tract
where is b12 absorbed in the gi tract
in the ileum of the small intestine
in the ileum of the small intestine