NEET BIOLOGY

Detailed explanation-1: -Recombination or crossing over occurs during prophase I. Homologous chromosomes – 1 inherited from each parent – pair along their lengths, gene by gene.

Detailed explanation-2: -Independent Assortment and Random Fertilization During metaphase I, the tetrads move to the metaphase plate with kinetochores facing opposite poles. The homologous pairs orient themselves randomly at the equator. This event is the second mechanism that introduces variation into the gametes or spores.

Detailed explanation-3: -Prophase I: The nuclear envelope breaks down. The chromatin condenses into chromosomes. Homologous chromosomes containing the two chromatids come together to form tetrads, joining at their centromeres (2n 4c). This is when “crossing over” occurs, which creates genetic variation.

Detailed explanation-4: -Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism’s offspring).

Detailed explanation-5: -One very important event in meiosis is crossing over, which occurs between prophase and metaphase I. Crossing over increases genetic variation. The haploid cells produced through meiosis are otherwise known as gametes. Gametes combine during sexual reproduction which also increases genetic diversity .