Question

How do variations arise in sexually reproducing organisms? Explain very briefly.

Answer 1

Variations in sexually reproducing organisms arise mainly due to genetic recombination during meiosis and fertilization. The key sources of variation include independent assortment of chromosomes during meiosis, crossing over or reciprocal recombination of linked genes in prophase I of meiosis, and the random fertilization of gametes. These mechanisms shuffle parental genes into new combinations, resulting in offspring with genotypes different from their parents, thereby creating variation within a species.