The relationship of the status of DNA to the cell cycle is illustrated in After mitosis,(M), when chromosomes are in their two-stranded(2C) configuration, there is a period of normal cell growth (Gap1 or G1) during which synthetic events, including those for subsequent DNA synthesis, take place.
DNA synthesis(S) results in a doubling of the chromosomes to a four-stranded(4C) configuration without cell division,and a second preparative growth period (G2) occurs before mitosis