The digestive system also known as the alimentary canal or gut is a long tube running from the mouth to the anus, with associated organs together with a number of associated glands that help in digestion. The human digestive system is well adapted to all of these functions.
Explain why most food must be digested?
Most food substances are insoluble in water and are made up of large complex organic molecules. They cannot pass through the wall of the villi and the capillaries. So digestion helps to convert large complex insoluble molecules into simple soluble molecules so that they can pass through the wall of the capillaries. There are five processes in digestion.
2. Digestion Mechanical digestion Chemical digestion