The Digestive System
purpose: to break down food into nutrients that can be absorbed by the circulatory system, which take them to the parts of the body where they are needed.
Four stages of digestion:
Ingestion: Take food in
Digestion: breakdown of food into molecules
Absorption: taking digested molecules into cells of the digestive tract
Egestion: removal of waste from the body
Mechanical digestion: This involves the breakdown of food particles into smaller pieces using the teeth, tongue, and stomach. Is a physical change.
chemical digestion: involves the use of enzymes. is a chemical change.
Human Digestion:
Digest food along a difestive tract called the alimentary canal, which is a one way flow complete with a mouth and anus, and food encounters specialized areas along the way for digestion.
Mouth: teeth, tongue,