1.16 The digestive system

Natural sciences

Grade 4

Life and way of living

Module 17

The digestive system

Learn about the digestive system and to name a few important organs in the system

Let us look at how the digestive system works: Your body needs food to grow and to remain healthy. A long canal runs from your mouth, right through the body to the opening where the food (residue) leaves the body again. The upper part of this canal is fairly straight, but the lower part is convoluted. Several things happen to the food while it travels along this canal.

When you chew your food, your teeth and tongue grind it and the saliva helps you to swallow it.

The food gets pushed through the oesophagus to the stomach. Muscles in the walls of the oesophagus contract automatically to do this. We speak of the peristaltic action of the oesophagus.

In the stomach, the food is mixed, ground and stirred by the muscles of the stomach wall.

Nutrients are removed from the food in the small intestine and are transported to other parts of the body by the blood.

What is left of the food goes through the large intestine, where water is mainly taken up, before the residue that is not needed leaves the body when the bowels are emptied.

Complete the illustration by filling in the captions.

Write a proper sentence to explain why babies are able to live on milk alone.

Memorandum

1. mouth
2. oesophagus
3. stomach
4. small intestine

5. large intestine