Enzymes and Digestion

It carries food from mouth to stomach.

It is adapted for transport

It is made up of a thick muscular wall.

This is a muscular sac with an inner layer that produces enzymes.

Its role is to digest food,especially protiens.

It has glands that produce enzymes which digest protiens.

Other glands in stomach wall produce mucus

The mucus prevents the stomach being digested by its own enzymes

This is a long muscular tube

Food is further digested in the small intestine by enzymes that are produced by its walls and by glands that pour their secretions into it.

The inner walls of the small intestine are folded into villi-which gives a larger surface area

The surface area of villi is further increased by microvilli, on the epithelial cells of each villus

This adapts small intestine for its purpose of absorbing products of digestion into the blood stream

• Absorbs water
• Often the water is reabsorbed by the secretion of digestive glands.
• Because there is little water within the large intestine, the food becomes drier and thicker,which then forms faeces.

This is the final section of intestines

It is where faeces are stored before it is removed through the anus in a process called egestion.  

• Positioned near the mouth
• They pass their secretions via a duct in the mouth
• The secretions contain amylase which breaks down starch into maltose.

• This is a large gland situated below the stomach
• Produces a secretion called pancreatic juice
• This secretion contains:

-Proteases to digest protiens

-Lipase to digest lipids

-Amylase to digest starch