<span>Point mutations are of two types: Substitutions of bases that are the change of one base of DNA by another. And Transitions that are replaced on a pyrrhic basis by another pyrrhic or a pyrimidine by another pyrimidine. Transversions: substitution of a pyrrhic base by another pyrimidine or vice versa. These mutations are negative because they affect only one of the nucleotides, and therefore, only one triplet of bases are affected. When the mutation does not affect the individual it is a silent mutation. Chromosomal mutations Changes in the structure of the diploid chromosomes, where one of the chromosomes has a mutation, will have another normal. They can hinder the process of meiosis in the carrier since it hinders the correct pairing of the homologous chromosomes. It would produce an unfeasible offspring or with mutations.</span>
Answer:
Option (e).
Explanation:
Meiosis may be defined as the process of cell division in which a single parent cell divides into four daughter cells. The chromosome number reduces to half in meiosis.
Crossing over is the process of exchange of genetic material between the homologous chromosomes of the non-sister chromatids. Crossing over will bring variation in the gametes. Hence, the absence of crossing over results in the formation of gametes with less genetic variation.
Thus, the correct answer is option (e).
