Science - The Digestive System

Digestion is the breaking down of food into smaller pieces

Physical Digestion

Chemical Digestion

This is when food is broken down into smaller pieces by the teeth, tongue and churning action of the muscles in the stomach

This is when food is broken into smaller pieces by enzymes

Enzymes are chemicals that speed up chemical changes in the body without itself being changed

They break down food

Salivary Amalyse

Starch

Sugar (Maltose)

Salivary Glands

Mouth

To chew food and mix it with saliva

Oesophagus (Food Pipe)

To carry food from the mouth to the stomach

Liver

To make bile which helps to break down fat

Stomach

To store food and mix it with digestive juices

Hydrochloric acid

Pancreas

To produce enzymes that pass into the small intestine and help to digest food

Large intestine

To pass water back into the blood and removes solid waste from the body

Small intestine

To put the broken down food into our blood

This is the muscular movement of food through the digestive system

To bite and cut the food

To crush and grind the food

To tear the food

To crush and grind the food

Eat less sugary food

Brush our teeth twive a day

Visit the dentist

This is when food is taken into the mouth

This is the breaking down of food into smaller pieces

It happens in the stomach

This is putting the digested food into the blood

The small intestine

1. It is approximately 6 metres long so this gives a large surface area for digestion and absorption

2. There are millions of villi which gives a huge surface area to help absorption of nutrients

3. The villi have thin walls and a rich blood supply which allows nutrients to be absorbed into the bloodstream

This is the removing of undigested food from the body

• Ingestion
• Digestion
• Absorption
• Assimilation
• Egestion