Answer to Question #98629 in Genetics for Alex

Question

What is crossing over in meiosis and what is the purpose of it?

Answer 1

Crossing over is the exchange of material between homologous chromosomes that occurs during meiosis and underlies genetic recombination (the emergence of new combinations of alleles), thus providing combinational variability in populations and providing material for natural selection. The exchange of regions of homologous chromosomes occurs by rupture and subsequent joining in a new chromatid order.