What type of digestive system do human beings have? Why don't humans reflect on our digestive system? The digestive enzymes of these animals cannot break down cellulose, but the microorganisms present in the digestive system can. When digesting proteins and some fats, the stomach lining must be protected from being digested by pepsin. Anyone who notices changes in their usual digestive processes should see a doctor, as this may indicate a health condition that requires treatment. Animals have developed different types of digestive systems to help digest the different foods they consume.
Chemical digestion continues throughout the digestive system with gastric acid in the stomach and pancreatic and other enzymes in the small intestine.