superior vena cava The superior vena cava carries deoxygenated blood to the heart. The blood comes from the upper body.

semi-lunar valves These valves prevent the blood from flowing back into the ventricles of the heart when it pumps.

right atrium This hollow chamber receives the deoxygenated blood from the body. (Via the superior vena cava and the inferior vena cava.)

right atrioventricular valve This valve prevents the blood flowing back into the atria when the heart pumps it into the ventricle.

right ventricle This hollow chamber pumps the deoxygenated blood to the lungs.

inferior vena cava The inferior vena cava carries deoxygenated blood to the heart. The blood comes from the lower body.

aorta The aorta carries the oxygenated blood to the body.

pulmonary arteries These vessels carry deoxygenated blood to the lungs.

pulmonary veins These vessels carry oxygenated blood from the lungs into the heart.

left atrium This hollow chamber receives the oxygenated blood from the lungs. (Via the pulmonary veins.)

left atrioventricular valve This valve prevents the blood flowing back into the atria when then heart pumps it into the ventricle.

left ventricle This hollow chamber pumps the oxygenated blood to the body.