| A | B |
|---|
| circulation | the movement of blood through the blood vessels |
| arteries | blood vessels that carry blood away from the heart |
| veins | blood vessels that carry blood back to the heart |
| capillaries | microscopic blood vessels that connect arteries and veins |
| chamber | a part of the heart |
| atrium | an upper chamber of the heart |
| ventricle | a lower chamber of the heart |
| valve | a door-like part that prevents blood from flowing backwards in the beart |
| pulse | a beat in arteries as blood spurts through them |
| stethoscope | an instrument used to listen to your heartbeat |
| centrifuge | a tool used for separating mixtures |
| plasma | the liquid part of the blood |
| hemoglobin | an iron-rich compound found in red blood cells |
| clot | sticky threads produced by th blood, which help stop bleeding |
| platelets | special cells that help blood to clot |
| bronchi | two tubes that branch from the lower part of the windpipe |
| alveoli | microscopic air sacs in the lungs |
| mucus | a sticky liquid lining the nose and windpipe |
| cillia | microscopic hairs found in the windpipe |
| diaphragm | a sheet of muscle under the lungs |
| inhaling | taking air in |
| exhaling | letting air out |
| perspiration | one of the liquid wastes of the body |
| pore | a tiny opening in the skin |
| urine | a liquid waste formed in the kidneys |
| urea | a waste product formed when proteins are used by the body |
