| A | B |
| ventricles | lower chambers of the heart |
| atrium | upper chambers of the heart |
| plasma | the liquid part of the blood |
| white blood cells | part of the blood that fight germs |
| red blood cells | part of the blood that carry oxygen |
| platelets | they help your blood clot when you get a cut |
| arteries | blood vessels that carry blood away from the heart |
| veins | blood vessels that carry blood to the heart |