Question

Given the end results of the two types of division, why is it necessary for homologs to pair during meiosis and not desirable for them to pair during mitosis?

Short answer

Answer: The pairing of homologous chromosomes during meiosis is necessary because it allows genetic recombination and promotes genetic diversity, which is essential for the survival and adaptation of a species. In contrast, pairing of homologs during mitosis is undesirable as mitosis aims to produce genetically identical daughter cells for growth, repair, and asexual reproduction. Pairing in mitosis could lead to genetic instability and cellular dysfunction.

Step-by-step solution

Understand the Objective of Meiosis and Mitosis

Meiosis is a type of cell division that results in four daughter cells, each with half the number of chromosomes as the parent cell. These daughter cells are called gametes or sex cells, and their purpose is for sexual reproduction. On the other hand, Mitosis is a type of cell division that results in two identical daughter cells, each having the same number of chromosomes as the parent cell. Mitosis occurs in somatic cells for growth, repair, and asexual reproduction.

Significance of Homologs Pairing in Meiosis

During meiosis, homologous chromosomes or homologs, pair up in a process called synapsis. The purpose of this event is to facilitate genetic recombination or crossing over between homologous chromosomes. Genetic recombination leads to new combinations of alleles on the chromosomes, resulting in greater genetic diversity in the offspring. This genetic diversity is essential for the survival and adaptation of a species.

Undesirability of Pairing Homologs in Mitosis

In mitosis, the objective is to produce two genetically identical daughter cells. Pairing of homologous chromosomes during mitosis would promote genetic recombination, which is not desired in somatic cell division because it would result in genetically different daughter cells. This would lead to issues in maintaining a stable genome and could result in harmful mutations or cell dysfunction.

Conclusion

In conclusion, homologs pairing during meiosis is necessary because it allows genetic recombination and promotes genetic diversity, which is essential for survival and adaptation of a species. On the other hand, pairing of homologs during mitosis is not desirable as mitosis aims to produce genetically identical daughter cells for growth, repair, and asexual reproduction. Pairing in mitosis could lead to genetic instability and cellular dysfunction.