Non-disjunction?occurs when chromosomes fail to separate during?meiosis
This occurs?spontaneously
The gametes may end up with?one extra copy?of a particular chromosome or?no copies?of a particular chromosome
These gametes will have a different number of chromosomes compared to the normal haploid number
If the abnormal gametes take part in fertilization, then a?chromosome mutation?occurs as the diploid cell will have the incorrect number of chromosomes
Chromosome mutations involve a?change in the number of chromosomes
An example of chromosome mutation is Down’s syndrome: Individuals with this syndrome have a total of 47 chromosomes in their genome as they have three copies of chromosome 21
Image showing how chromosomes failing to separate properly during meiosis can result in gametes with the incorrect number of chromosomes
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