The heart pumps oxygenated blood to the body and deoxygenated blood to the lungs. In the human heart there is one atrium and one ventricle for each circulation, and with both a systemic and a pulmonary circulation there are four chambers in total: left atrium, left ventricle, right atrium and right ventricle.he essential components of the human cardiovascular system are the heart, blood and blood vessels. It includes the pulmonary circulation, a loop through the lungs where blood is oxygenated; and the systemic circulation, a loop through the rest of the body to provide oxygenated blood.