Once the DNA in a cell is replicated, the cell can divide into two cells, each of which has an identical copy of the original DNA. DNA replication is the process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules.
The heart is a vital organ located in the center of the chest with a slight tilt to the left. Using rhythmic muscle contractions, it circulates blood through veins and arteries, which supplies tissues with oxygenated blood and disposes waste.
The heart is a muscular organ about the size of a fist, located just behind and slightly left of the breastbone. The heart pumps blood through the network of arteries and veins called the cardiovascular system. The heart has four chambers: The right atrium receives blood from the veins and pumps it to the right ventricle.