Physical and chemical digestion
Digestion, the process of breaking down food into usable parts, has two separate types:
Physical digestion uses physical means to reduce the size of pieces of food. This can also be called mechanical digestion.
Chewing with the teeth is a form of physical digestion.
By breaking the food into smaller pieces, physical digestion increases the surface area that enzymes can attack.
During chemical digestion, enzymes break large molecules into small molecules that can be absorbed and used by the body.
Proteins are composed of hundreds of amino acids. Chemical digestion separates protein into its amino acids, which can then be used to make new proteins.