Mitosis (Cambridge (CIE) IGCSE Co-ordinated Sciences (Double Award)): Revision Note

New Cells are Made by Mitosis: Extended

Extended Tier Only

• Most body cells have two copies of each chromosome

• We describe these cells as diploid

• When cells divide, the replication of chromosomes happens beforehand where chromosome numbers are doubled

• This ensures that when the cell divides in two, each new cell still has two copies of each chromosome (is still diploid)

• This type of cell division is known as mitosis and is used for:

  • growth

  • repair of damaged tissues

  • replacement of cells 

  • asexual reproduction 

• Mitosis is defined as:

Nuclear division giving rise to genetically identical cells

The process of cell division by mitosis