what is the major function of the jejunum
Function. The main tasks of the jejunum are: 1  cleavage of nutrients (e.g. by amylase, proteinase). 2  absorption of lipophilic nutrients (proteins, fats, cholesterol and the fat-soluble vitamins A, D, E and K). 3  absorption of water (about 90% of the secreted water, 6 to 8 liters/day).