A CARBOHYDRATES, PROTEINS AND LIPIDS B CALCIUM IRON AND FOLATE Calcium Iron Carbo- Du odeum Folate Duodenum hydrates, Jej unum Calcium proteins, ← Calcium High absorption Moderate absorption C BILE ACIDS D COBALAMIN Low absorption Very low absorption Duodenum Bile Jejunum Cobalamin 营养物质的吸收部位 Sites of nutrient absorption营养物质的吸收部位 Sites of nutrient absorption