Digestion of Protein (Cambridge International IGCSE Biology)

Digestion of protein: Extended

Spec point — Describe the digestion of protein by proteases in the digestive system: (a) pepsin breaks down protein in the acidic conditions of the stomach (b) trypsin breaks down protein in the alkaline conditions of the small intestine

Digestion of protein: Extended

Extended Tier Only

• Proteases are a group of enzymes that break down proteins into amino acids in the stomach and small intestine (with the enzymes in the small intestine having been produced in the pancreas)

The digestion of proteins

• Protein digestion takes place in the stomach and duodenum with two main enzymes produced:

  • pepsin is produced in the stomach and breaks down protein in acidic conditions
  • trypsin is produced in the pancreas and secreted into the duodenum where it breaks down protein in alkaline conditions