<Li> <P> Dog jejunum (magnified 100-fold) </P> </Li> <P> Dog jejunum (magnified 100-fold) </P> <P> The lining of the jejunum is specialized for the absorption, by enterocytes, of small nutrient particles which have been previously digested by enzymes in the duodenum . Once absorbed, nutrients (with the exception of fat, which goes to the lymph) pass from the enterocytes into the enterohepatic circulation and enter the liver via the hepatic portal vein, where the blood is processed . The jejunum is involved in magnesium absorption . </P> <P> In fish, the divisions of the small intestine are not as clear and the terms middle intestine or mid-gut may be used instead of jejunum . </P>

Function of the jejunum in the digestive system