Meiosis is a type of cell division that reduces the chromosome number from 2n to
ID: 37136 • Letter: M
Question
Meiosis is a type of cell division that reduces the chromosome number from 2n to n to make gametes viable for reproduction in humans. I know that during meiosis, there is independent assortment and crossing over that occurs, which help to make more genetically individual organisms.
My question is, why don't haploid gametes go through mitosis to reproduce instead of diploid germ cells going through meiosis to create more gametes, without considering crossing over and independent assortment? This is just my opinion, but meiosis seems like a much more energy intensive process. After the germ cells go through meiosis once to create the gametes, I do not see why the gametes don't then just multiply via mitosis (again, not considering crossing over/independent assortment.)
Is there any specific reason, other than to create more genetically diverse people, that gametes do not undergo mitosis to multiply rather than germ cells undergoing meiosis to make more gametes?
Explanation / Answer
To me, your question sounds like "what are the possible advantages of sexual reproduction over asexual reproduction?" but in the meantime you're saying that you're not interested neither in the advantage of recombination nor in the advantage of "independent assortment". I don't quite see what you mean by "independent assortment" in this context.
I just want to say some words about some "proximate" possible explanations of the evolution of sex. It's been suggested that meiosis have evolved in order to repair damage in double stranded DNA. Also, it's been suggested that meiosis is important for the problems of telomere length also.
You might be interested to have a look to the evolution of bi-phasic life cycles and, more globally speaking to the evolution of sex.