Question

In what ways does meiosis generate genetic variation?

Answer 1

Hint: During cell division, the nuclear division processes of mitosis and meiosis take place. Mitosis is the process of body cell division, whereas meiosis is the process of sex cell division. Mitosis produces diploid daughter cells, whereas meiosis produces haploid daughter cells. Meiosis is also called a reductional division.

Complete answer:
Meiosis creates genetic variety by allowing novel combinations of variants to develop in the gene pool through a process known as crossing over. During prophase of meiosis I, homozygous chromosomes come together and exchange genetic material.

Meiosis I and II :-
Meiosis is a process that occurs in two generations of cells. Each chromosome is copied during normal cell division, or mitosis, resulting in chromosomes with twin sister chromatids. During mitosis, these linked chromatids split to generate the next generation of identical chromosomes. The chromatids do not separate during meiosis I, therefore each daughter cell receives only one copy of each chromosome (haploid number), with each copy including two chromatids. The chromatids separate and are dispersed to each resultant gamete during meiosis II.

Crossing over :-
The double-chromatid homologous pairs of chromosomes cross over and frequently swap chromosomal segments during prophase of meiosis I. This recombination creates genetic diversity by allowing genes from both parents to mix, resulting in chromosomes with distinct genetic complements. Non-sister chromatids exchange information. Because genes frequently interact, a new combination of genes on a chromosome can result in kids with new features.

Reduced to a haplotype :-
During meiosis I, the duplicated chromatids remain linked, thus each daughter cell only obtains one chromosome from each homologous pair. The diploid number is reduced to haploid, and each chromosome's distribution is random. This indicates that a particular chromosome has an equal chance of being distributed to either of the two daughter cells. The gametes produced by meiosis II have different combinations of maternal and paternal chromosomes as a result of shuffling the genetic deck in this way, boosting genetic variety.

Chromatid Assortment at Random:-
During meiosis II, when the sister chromatids separate and are randomly dispersed to the daughter cells, the gametes, a third source of genetic variety emerges. In meiosis I, crossing over results in non-identical chromatids in meiosis II chromosomes. The centromere that connects each chromatid pair dissolves during anaphase of meiosis II, resulting in two chromosomes of each type. Each gamete has a potentially unique combination of genetic material since the outcome of which chromosome goes to which gamete is unpredictable.

Note:-
Fertilization allows each parent to contribute a unique set of genes to a zygote at random, resulting in genetic variety. While fertilisation is not a part of meiosis, it is dependent on the production of haploid gametes by meiosis. The diploid number is restored by the fertilised cell. Without meiosis, the number of chromosomes per cell in each generation of progeny would double, resulting in unstable conditions that could jeopardise a species' survival.