Chromosome number is a characteristic feature of members of a particular species
Chromosome Number can change in these two ways
- Organisms with different diploid numbers are unlikely to be able to interbreed (cannot form homologous pairs in zygotes)
- In cases where different species do interbreed, offspring are usually infertile (cannot form functional gametes)
- For instance, a horse (diploid = 64) and a donkey (diploid = 62) may produce an infertile mule (non-diploid = 63)
Chromosome Number can change in these two ways
- Chromosome splitting will inrease the number of chromosomes
- Chromosome fusing will decrease the number of chromosomes