What is crossing over? Write the significance of crossing over.

The process which results in recombination by exchange of the segments between non-sister chromatids of homologous chromosomes is called as crossing over. It takes place in pachytene stage of prophase-I of meiosis. Crossing over occurs between these chromatids in the region of chiasma.

Significance of crossing over:

1. Crossing over leads to the production of a new combination of genes.

2. It plays an important role in the process of evolution.

3. The crossing over frequency helps in the construction of genetic maps.

4. It gives us the evidence for a linear arrangement of linked genes in a chromosome.