The Cell Cycle
(Timing of somatic cell division)

This follows the pages about an animal cell and the introduction to cell division. It accompanies the page about mitosis.

The whole cycle of somatic cell division lasts from 8 to 24 hours in humans.

The part of the cell cycle during which the nucleus of the cell is dividing (which is called mitosis) takes about 10% of the total time for the full cycle. The cytokinesis phase takes about half of that time.

Most of the cell cycle is the period during which the cell is not dividing, which is called interphase.

A pie-chart is a simple way to represent this information:

Above: Typical timing of somatic cell division.

Summary of the Stages of the 'Cell Cycle' for Somatic Cells

From the page about mitosis: In all somatic cells (i.e. all cells in the non-reproductive parts of the body = all cells except for those of the gametes) the 'cell cycle' consists of two periods:

• Interphase also known as 'interkinesis', is the period during which the cell is not dividing.
  This does not mean that little is happening. Interphases are active periods during which cells perform all the functions necessary for life and synthesise DNA (deoxyribonucleic acid) so that both of the new cells formed by the mitotic phase will contain a complete copy of the original in order to have everything needed.
  
• Mitotic phase (M) when the cell is dividing.
  The mitotic phase of the 'cell cycle' consists of two stages:
  • Mitosis
    Mitosis is the division of the cell nucleus, and is followed by:
  • Cytokinesis
    Cytokinesis is the division of the cytoplasm of the cell into two daughter cells.

For further detail about mitosis see the diagram illustrating mitosis.