Question

cytological basis of crossing over​

Answer 1

Cytological basis of crossing over. ... Crossing over is a process that produces new combinations of genes by exchanging segments between non-sister chromatids of homologous chromosomes normally reciprocally but sometimes unequally.

Answer 2

The cytological basis of crossing over is to form new gene combinations where the chromatids  that are non-sisters exchange segments in a reciprocal manner and at many times non-equally.

The  chromosomal pars get interchanged to form a new variety of genes.

This was termed as a crossover by  Morgan and it occurs in the DNA levels as well as the chromosomal levels.

The physical distance of the genes is a factor for the crossover.