Question

What would happen if mitosis occurred in gametes of one parent instead of meiosis? How would this affect the offspring of these parents?

Answer 1

Mitosis is a type of equational division that means the daughter cells that are formed has the exact number of chromosomes as that of parent cell while meiosis is a reductional division that means the daughter cells have half the number of the chromosome as that of the parent cell.

When meiosis occurs during gamete formation it means progenitor cell which is diploid in nature divides to form gametes which are haploid daughter cells. When the gametes from two parents fuse to form a zygote which is a diploid cell and it later forms an offspring that how the ploidy is maintained throughout the species. If there is a mitosis division during the formation of gametes then the gametes formed will have a diploid number of the chromosome as a result when the fusion and formation of zygote will take place it will be tetraploid in nature as a result the offspring born from those parents will show polyploidy.

Offspring showing polyploidy will have a various effect due to having extra sets of the chromosome than the number of diploid cells. Due to an extra set of the chromosome, the segregation will not take properly during cell division as a result the offspring can be sterile. It can also lead to various genetic diseases. It can also disrupt the cell enlargement and its nuclear effects and the cell division either meiosis or mitosis will lead to the production of aneuploid cell and epigenetic instability which can cause non-additive gene regulation.