| A | B |
| Atria | The smallest chambers in the heart |
| Ventricles | The larger chambers of the heart |
| Valves | They stop blood flowing backwards |
| Arteries | They take blood away from the heart |
| Veins | They take blood to the heart |
| Lungs | This is where gas exchange happens |
| Stomach | This is where food is mixed with acid |
| Brain | This controls the entire body |
| Heart | This pumps blood around the body |
| Circulation | The series of blood vessels in the body |
| Red blood cell | This is an oxygen taxi |
| Oxygen | We need this for respiration |
| Carbon Dioxide | This is a waste product |