| A | B |
|---|
| Cardiovascular system | organ system that conveys blood to and from all parts of the body |
| veins | large blood vessels that carry blood from the tissues back toward the heart |
| arteries | large, thick-walled muscular vessels that carry oxygenated blood away from the heart |
| vessels | tube containing or conveying blood |
| cells | basic units of all organisms |
| cardiac muscle | type of involuntary muscle found only in the heart |
| electrical | presence of an uncancelled, excess of either positive or negative charge |
| myocardial | the muscular substance in the heart |
