Question

1.What is the significance of chromosome number, given the role the cells produced in meiosis have in reproduction?

2. Explain the benefit of this diversity between daughter cells for sexually reproducing species.

Answer 1

1. Meiosis is a type of cell division that occurs specifically in germ cells to produce haploid germ cells from diploid precursor cells. That's why it is also called as reductional cell division.

These haploid germ cells or gametes of opposite gender fuse to produce a diploid organism. So the gametes must contain half the total chromosome number in order to give rise to viable egg or sperm. These gametes through those half chromosomes carry all the information required for the survival and functioning of it when it will fuse with the other gamete to produce an offspring.

So to achieve this haploid state, meiosis is the only mode of cell division that through reduction mode of cell division segregates the paired chromosomes from parental germ cells to equally distributed half the set of all chromosomes in the gametes.

This chromosomal segregation by meiosis produces a diversed gamete pool because of the recombination process occurring between the chromatids of the chromosomes.

2. Meiotic cell division results in production of large diversed gametes containing unique genetic composition as a result of recombination that occurs during prophase-I of meiosis between nonsister chromatids of homologous chromosomes and independent assortment of the gametes.

This type of division is highly beneficial in the sense that it restricts the mutations to a segment of chromosome i.e., gene not to whole chromosome as that of mitosis.

This recombination resulting in an unique gamete makes every zygote unique having unique characteristics.