Replication is the process by which nucleic acids such as deoxyribonucleic acide (DNA) or ribonucleic acid (RNA) are copied. The current method of replication was first proposed by James Watson and Francis Crick in 1953. They suggested that DNA was replicated by a semiconservative method in which each strand of DNA served as a template for new strands. In the late 1950s, this theory was confirmed through experiments performed by Matthew Meselson and Franklin Stahl. In their experiment, they grew E. coli bacteria in a medium, containing a heavy isotope of nitrogen. The bacteria naturally incorporated the heavy nitrogen into their DNA. The bacterial cultures were then placed in a lighter nitrogen, which enabled Meselson and Stahl to follow the production of new DNA and confirmed the semiconservative replication model.

DNA replication begins with a double strand of DNA. This structure, or parent molecule, is made up of two...