Somatic cells of a species of dragonfly have a diploid number of 48. If a cell in the ovary of this dragonfly was undergoing cell division, what type of cell division would be taking place? How many sister chromatids would there be in each cell at metaphase II? How many chromosomes would there be in each egg cell?

a) Meiosis

b) 48 sister chromatids

c) 24 chromosomes

Explanation:

Dragonflies have 48 chromosomes in their somatic cells. These cells are diploid. However, in gonads such as ovaries and testis, there are gametes that are haploid and they are produced by meiosis. So, the type of cell division that is taking place in ovaries is meiosis.

Before meiosis, cells undergo DNA replication, that means that there is a duplication of genetic material. So, if there are 48 chromosomes initially, after replication it will be 96 chromosomes. During meiosis, this cell with 96 chromosomes will have a reduction by half in meiosis I. That is, after meiosis I, there will be 48 sister chromatids and meiosis II will take place. In meiosis II, and metaphase II there will be 48 chromatids that will be separated at the end of meiosis II to generate haploid gametes. In this case, eggs with 24 chromosomes.