WAEC Biology 2014 Theory — Question 6

Model answer

In the stomach: the enzyme pepsin, in the acidic gastric juice, converts the protein in the fish to peptones. In the duodenum: the enzyme trypsin (released into the duodenum in the pancreatic juice) converts the peptones to polypeptides. In the ileum: the enzyme peptidase (erepsin), in the intestinal juice, converts the polypeptides to amino acids, which are then absorbed into the bloodstream through the villi.