__7_ refers to the blood flow to and from the lungs
__5_ high blood pressure, elevated to over 140/90 (systole/diastole)
__3_ the relaxed phase of the heartbeat; the lower number of blood pressure measurement
__2_ blood that is oxygen-depleted; blood containing low levels of oxygen
__8_ deoxygenated blood is returned from all over the body to the heart, it is then pumped on to the lungs via the pulmonary artery
6___ blood that is rich in oxygen; blood containing high levels of oxygen
4___ the protein in red blood cells used to carry oxygen in the blood
1___ the coronary arteries supply blood to the heart muscle
