Mitosis

• Step 1 - Nucleus contains long uncoiled chromosomes. Each chromosome doubles to form 2

  identical chromatids.
• Step 2 - Chromosomes shorten and coil up. Nuclear membrane starts to disappear.
• Step 3 - Chromatids line up at the equator of the cell and spindle fibres attach to the centromeres.
• Step 4 - Pair of identical chromatids are pulled apart by spindle fibres to opposite ‘poles’ of the cell.
• Step 5 - New nuclear membranes form and the Cytoplasm divides.
• Mitosis produces daughter cells with the same number of chromosomes as the parent cell.
• The daughter cells are genetically identical to the parent cells.
• The daughter cells have a full complement of chromosomes and are called diploid.
• Any change or loss of information would result in cells which could not function properly.
• Mitosis produces the cells which allows growth and repair, e.g.

  
  

  -to replace worn out red blood cells

  
  

  -to heal cuts and broken bones.

  
  

  -to allow growth from a child to adult.