chemical digestion is a series of chemical reactions that break large chunks of food into proteins, carbohydrates, and fats.

Chemical digestion is a series of chemical reactions that break down large chunks of food into smaller molecules such as proteins, carbohydrates, and fats. This process primarily involves enzymes and water molecules in a reaction called hydrolysis, which breaks chemical bonds in food molecules to make them small enough for absorption by the body's cells. Proteins are broken down into amino acids, carbohydrates into simple sugars like monosaccharides, and fats into fatty acids and monoglycerides. Chemical digestion begins in the mouth with enzymes in saliva starting the breakdown of carbohydrates and continues in the stomach and small intestine where digestive enzymes further degrade proteins, fats, and carbohydrates for absorption. The stomach uses gastric juices including hydrochloric acid and enzymes like pepsin to initiate protein digestion. In the small intestine, enzymes from the pancreas and bile from the liver complete the digestion of all macronutrients.