What triggers meiosis in gonadal cells?

Question

What specific biochemical processes are involved in inducing meiosis rather than mitosis? Why are gonadal cells the only cells in the human body which do undergo meiosis?

Answer 1

Hello,

So meiosis is cellular reproduction that produces two unique haploid daughter cells. Meiosis only occurs in preparation to form a zygote. Mitosis occurs in every somatic cells (basically every cell in the body other than the gonads). Meiosis 1 is completed in utero for females and meiosis 2 is completed once a month during menstruation. So the pathway here is menstruation. For males, meiosis occurs every time sperm is produced, usually beginning after puberty.

The reason that only gonadal cells go through meiosis is because these gamete cells need to be haploid cells, and meiosis produces haploids. Two haploid cells (one coming from a female in the form of an ova and the other coming in the form of sperm from a male) come in contact, the sperm haploid cells fertilizes the ova and creates a diploid zygote. Once the zygote forms, the zygote undergoes mitosis since it is not a diploid cell.

Hopefully this was helpful. If you need any further clarification, I would be happy to do so.