Overview of Mitosis

  • Mitosis is a type of cell division that results in two genetically identical daughter cells, each with the same number of chromosomes as the parent cell.
  • This process occurs in somatic cells or body cells and is vital for growth and repair in multicellular organisms.
  • Mitosis is divided into several stages: prophase, prometaphase, metaphase, anaphase, and telophase, followed by cytokinesis.

Stages of Mitosis


  • This is the initial stage of mitosis. Here, the chromosomes, which were loosely arranged within the nucleus, condense and become visible.
  • Each chromosome at this stage is composed of two identical strands, called sister chromatids, held together at the centromere.


  • During prometaphase, the nuclear envelope breaks down and disappears.
  • The centrosomes, containing two centrioles, move to opposite poles forming the mitotic spindle.
  • The spindle fibres attach to the centromere of the chromosomes.


  • The chromosomes line up along the equatorial plane or the metaphase plate, the imaginary line in the middle of the cell.
  • Each chromosome is held in place by spindle fibres attached to the centromere.


  • During anaphase, the sister chromatids are pulled apart towards opposite poles by shortening of the spindle fibres.
  • By the end of this stage, each pole of the cell has a complete set of chromosomes.


  • During telophase, a new nuclear envelope starts to form around the chromosomes at each pole.
  • Chromosomes decondense and return to their thread-like form, and the spindle fibres disappear.


  • Cytokinesis is the final phase of cell division, occurring after mitosis.
  • It involves the division of the cell’s cytoplasm, resulting in two separate daughter cells.

Significance of Mitosis

  • Mitosis ensures genetic continuity, as the daughter cells receive an exact copy of the genetic material from the parent cell.
  • This process is essential for growth and repair of tissues in multicellular organisms.
  • Mitosis also plays a crucial role in asexual reproduction among single-celled organisms.

Mitosis and Genetic Stability

  • Errors in mitosis can lead to cells with an incorrect number of chromosomes (aneuploidy), which can cause various genetic disorders.
  • Cancer is often the result of cells dividing uncontrollably due to mistakes in mitosis.