In: Biology
Identify THREE ways that sexual reproduction increases genetic variability. For each, explain how it increases genetic diversity among the offspring.
Sexual reproduction involves production of haploid gametes by both the male and female partner which when combined produces a diploid organism.
During the production of these haploid gametes by both the male and female , by meiosis , various modifications occur in the chromosomes , which contributes to genetic diversity.
1) independent assortment -
During meiosis , the homologous chromosomes are separated during anaphase I. These chromosomes get aligned independently during the metaphase I.these arrangement varies from cell to cell. This can cause variation in the expression of the traits.
2) Crossing over -
This can occur in homologous chromosomes , where they exchange small fragments of the DNA during prophase l. This can be explained by the reassemble of the offspring's eye colour to that of father and hair colour to that of the mother.
3) fertilization -
During sexual reproduction , the male gametes enter the female reproductive organ and are numerous in number unlike female gamete , where a single egg is produced every cycle . This provides diverse possibilities and the resultant cell may have variations that have occurred due independent assortment and crossing over.