Question

Which mechanism of genetic variation results from the exchange of gene segments between non-sister chromatids?

Answer 1

The tight pairing of the homologous chromosomes is called synapsis. In synapsis, the genes on the chromatids of the homologous chromosomes are precisely aligned with each other. An exchange of chromosome segments between non-sister homologous chromatids occurs and is called crossing over.

Answer 2

- some google site but wont post the link

Answer 3

and here