Page 58 - FOUNDATIONS FOR LIFE; EXPLORING GOD’S UNIVERSE

Science Y6 – Marvellous Me – lesson 13

Everyday we breathe about 15,000 to 20,000 litres of air. When the air is polluted, it can harm our lungs.

Why do we breathe?

As soon as a baby is born God has designed the lungs to breathe for the first time so the baby cries and takes
in air. The ribs protect the lungs. We breathe through the trachea and from there the air passes into the
bronchial tubes into the lungs.

Your body is made up of tiny cells which need oxygen. Oxygen allows the cell to get energy from the food you
eat. Oxygen in the air is brought into your lungs. That's when your blood picks it up and brings it to your cells.

Carbon dioxide is a waste product of your cells. It is very dangerous if it builds up in your body. Your blood
carries the carbon dioxide from your cells to your lungs, to let you breathe it out.

Why do I get out of breath?

When we exercise, our cells are working harder, and they need more oxygen. They also produce more carbon
dioxide. That's why you breathe faster when you exercise! When you're exercising, your heart beats more
quickly. That's so that the blood can carry oxygen to your cells faster!

Your heart and lungs work together to make sure every cell in your body gets enough oxygen.

What happens when we rest?

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