DNA replication is the process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules.
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.
The heart is a muscle that pumps blood throughout your body. The blood carries oxygen and nutrients that your body needs to work correctly.he function of the heart is simple. It keeps blood circulating throughout the body by: 1  Pumping blood through your lungs to make certain that the blood supply is constantly refreshed with oxygen and carbon dioxide is removed, and. 2  Pumping blood through your body to meet its demand for oxygen and nutrients.