Alimentary Canal: Secretion and Digestion, Special Digestive Functions, and Absorption

Abstract

The process of digestion involves all of the mechanical and chemical changes that ingested food must undergo before it can be absorbed in the intestines. Mechanical changes include swallowing, maceration, and grinding of food in the muscular stomach; chemical digestion consists of secretion of enzymes from the mouth, stomach, intestines, and pancreas, of bile from the liver, of hydrochloric acid from the stomach, and of bacterial action.