The sequence of events in a cell resulting in the formation of two complete daughter cells. In addition to the observable changes during *mitosis
, biochemical processes occur in the nucleus and cytoplasm. *Cytokinesis
is followed by a growth phase (G1 phase) during which there is a high rate of RNA formation and protein synthesis. A lag phase of variable duration is followed by a period of DNA replication and histone synthesis (S phase) as the chromosomes divide into chromatids. Finally there is a short growth period (G2
phase) before prophase of mitosis begins. The length of each period varies considerably. In actively dividing cells in culture the full cycle takes twenty four hours while in living tissue the time taken to double the number of cells can be as short as eight hours.