A cell cycle is the sequence of events in which the genome of the cell is duplicated, other constituents of the cell are synthesized, and finally, the cell is divided to form two daughter cells. During this cell cycle, DNA synthesis takes place only during a single phase called as S-phase or Synthesis phase, while cytoplasmic increase or cell growth is a continuous process which takes place almost during the complete cell cycle.
In the cell cycle, mainly 2 phases are there as Interphase and M-phase. During interphase contents of the cell are duplicated while M-phase is an exact phase of division called Active Mitosis. In the cell, cycle interphase consumes more than 95% time period of cell cycle while active mitosis or M-phase consumes only 4 – 5% time period. Duration of the cell cycle, interphase and M-phase vary cell to cell and organism to organism. Usually, M-phase lasts for 10 minutes to a few hours. In human cells, cell cycle lasts for 24 hours while M-phase lasts for only 1 hour.