The special process of cell division by which part exchange takes place between the non-sister chromatids of homologous chromosomes is known as crossing over. Chromosome gets the new arrangement of genes.
Types of crossing over On the basis of the number of chiasma, crossing-over may be of two types-
(1) Mono-crossing-over and
(1) Mono-crossing over: In this case chiasma is formed only in a single point.
(2) Di-crossing over: In this case chinsma is formed in two different points.
Importance of Crossing-over:
- Part exchange occurs in between the homologous chromosomes coming from the parents. This part exchange results the changed characteristics in the new generation.
- Crossing-over brings about variation in the new generation which accelerates the formation of new species through evolution.