After DNA has been replicated, the nucleus must first be divided before the cell can split into two

• Nuclear division is necessary to ensure that both daughter cells have genetic material and are not anucleate
  

• Anucleate cells are unable to synthesise proteins needed to maintain the structure and metabolic activities of a cell, resulting in an extremely limited lifespan (e.g. red blood cells)
  

There are two distinct ways the nucleus can be divided, according to the function of the daughter cell:

• Mitosis: A single nuclear division that produces genetically identical daughter cells with the same number of chromosomes as the parent cell
  

• Meiosis: A process of two nuclear divisions that produce genetically distinct daughter cells with only half the number of chromosomes as the parent cell 
  

Mitosis

Mitosis is a process of asexual reproduction that results in the production of genetically identical daughter cells (clones)

• It involves a single nuclear division that ultimately results in the production of two daughter cells
  

  • The single nuclear division separates the sister chromatids into two identical sets of chromosomes
    

• The chromosome number and genome remains unchanged between the parent cell and daughter cells
  

• In multicellular organisms, it is used for cell proliferation (generates new body cells for growth and tissue repair)
  

• Malfunctions in mitosis can lead to the development of cancers (uncontrolled cell division of body cells)
  

Meiosis

Meiosis is a process of sexual reproduction that results in the production of genetically distinct daughter cells (promotes variation)

• It involves two nuclear divisions that typically result in the production of four daughter cells
  

  • The first nuclear division divides the total number of chromosomes in two (reduction division)
    

  • The second nuclear division separates the sister chromatids that were produced by DNA replication
    

• The chromosome number is halved from parent cell to daughter cell (diploid → haploid)
  

• In multicellular organisms, it is used to create sex cells (gametes) in order to generate offspring that are genetically distinct
  

• Malfunctions in meiosis can lead to aneuploidy conditions (offspring with an abnormal total number of chromosomes)
  

Mitosis versus Meiosis