Question

How is variation bought in the progeny in the sexual reproductive organisms?

Answer 1

In sexually reproductive organisms, the process of meiosis occurs in the germ cells which results in the formation of haploid gametes. Meiosis involves the process of crossing over in which the non-sister chromatids exchange their DNA and this results in genetic recombination. When the haploid gametes fuse, the genetic recombination results in variation of genotype and phenotype. Further, whenever DNA is replicated, there are chances of mutations that also produce variations.