Protein digestion takes place inside the belly and duodenum. Pepsin, which is secreted via means of the belly, and trypsin and chymotrypsin secreted via means of the pancreas, spoil down meal proteins into polypeptides. 

The digestive enzymes are normally secreted as their inactive precursors referred to as zymogens. For example, trypsin is secreted via way of means of the pancreas inside the shape of trypsinogen, which is activated inside the duodenum via way of means of enterokinase to shape trypsin. Proteins are then broken up into smaller polypeptides by trypsin.