the digestive system

The digestive system - a long muscular tube in which enzymes speed up breakdown of food (eg. fats, proteins, starch) into smaller molecules so that they can pass through the walls of the small intestine and into the bloodstream.

mouth - to prepare food for digestion. salavary glands secrete saliva into the mouth through ducts.

gullet - the muscles of the wall contracts as food is pushed forward this is called peristalis.

stomach - has layers of muscle that contract in different directions causing the stomach to twist and turn

pancreus - makes enzymes that digest all three of the main classes of food. a protease, a carbohydrase and a lipase.

small intestine - is where digestion is completed, it is the longest part of the digestive system

large intestine - much of the water is absorbed here. cellulose and other ingestible substances are stored as feises before exeting the body.

protease - proteins

carbohydrease - carbohydrates

lipease - fats