Zoology - Digestion and Absorption Question with Solution | TestHub

Pancreatic juice and bile open through a hepatopancreatic duct into the duodenum where intestinal juice also mixes with it. Duodenum is the site where maximum digestion takes place. First the pancreatic juice acts on the macromolecules and then intestinal juice acts on them to finally convert into micromolecules that can be readily absorbed. These are done with the help of various enzymes present in the juices. Pancreatic juice contains enzymes in an inactive form that become activated by enterokinase (an enzyme of the small intestine). The inactive enzymes are trypsinogen, chymotrypsinogen, procarboxypeptidases, amylases, lipases, and nucleases. Enterokinase first activates trypsinogen to form trypsin and then this enzyme activates the other pancreatic enzymes. Trypsin, chymotrypsin, and carboxypeptidases act on proteins. Amylases act on starch. Lipases act on fats. Nucleases act on nucleic acids. Lipases are present in gastric juice, pancreatic juice and succus entericus too.