Chromosome mutations

• What is Non-Disjunction?


  When the chromosomes or chromatids do not slit equally during anaphase
• What are the 2 forms of Non-disjunction?

  1. Aneuploidy- Changes in the number of individual chromosomes.
  2. Polyploidy-Changes in whole sets of chromosomes.
• When do polyploidy changes occur?

  When organisms have 3 sets of chromosomes rather than the usual 2
• What occurs during aneuploidy Non-disjunction?

  • Changes in the number of individual chromosomes.
  • Sometimes individual homologous pairs of chromosomes fail to separate during meiosis.
  • This is non-disjunction and usually results in a gamete having one more or one fewer chromosomes.