define digestion

Digestion is the process by which food is broken down into smaller, simpler molecules that can be absorbed and used by the body. It involves both mechanical and chemical processes that occur in the mouth, stomach, and small intestine. Mechanical digestion involves the physical breakdown of food through chewing and the muscular contractions of the stomach and intestines. Chemical digestion involves the breakdown of food molecules by enzymes and other substances in the digestive system. The end result of digestion is the release of nutrients such as carbohydrates, proteins, and fats that can be absorbed into the bloodstream and transported to cells throughout the body to provide energy and support vital functions.