The heart is a four-chambered muscular pump which pumps blood round the circulatory system.

The right side of the heart pumps de-oxygenated blood to the lungs to pick up oxygen.

The left side of the heart pumps the oxygenated blood from the lungs around the rest of the body.

1. Deoxygenated blood enters through the vena cava into the right atrium

2. It’s then pumped through a valve into the right ventricle chamber

3. And then up through the pulmonary valve into the pulmonary artery towards the lungs

4. Oxygenated blood enters through the pulmonary veins into the left atrium

5. It’s then pumped through a valve into the left ventricle

6. And then through the aortic valve and out of the aorta to the rest of the body