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Cell identification - germ cells in haploid male antsModerator: BioTeam
5 posts • Page 1 of 1
Cell identification - germ cells in haploid male antsI found it interesting that male ants (and others in that group) are born haploid. I wondered how these cells go thru the processes of mitosis and meiosis. I didn't see a problem with mitosis but don't think meiosis can process haploid cells to produce haploid sperm cells.
The male ants obviously mate, so it works somehow. In the female ant, I assume the specie's genes instruct standard meiosis to be used. Germ cells are modified two times before they become spermatids. The spermatids go through a maturation process before becoming sperm cells (gametes), at least in some organisms. http://www.biology-questions-and-answer ... nesis.html I assume the male haploid germ cells and other intermediate cells are identified in some way, so they can't be utilized as sperm cells. What processes are utilized to convert the male haploid germ cells to sperm cells?
Female ants don't make sperm cells.
Other than that, I'm pretty sure gametogenesis in haploid insects only uses mitosis. There isn't much information about this around, so you should do your own investigation! Let us know the results if you do. "Every cell is a triumph of natural selection." Carl Sagan
Its not always necessary that ant males are haploid. It depends on the inbreeding ratio of the species. The increase in inbreeding gives rise to diploid males, but mostly these diploid males are infertile as the generate diploid spermatozoa.
http://en.wikipedia.org/wiki/Haplodiploid_sex-determination_system The process of spermatogrnesis in Hymenopteran males (Haploid or Diploid) is unusual. The meiosis never take place in their gonads. But the mitotic process by which primary spermatocyte divides is unequal cytoplasmic division. It gives rise to a Spermatide and one polar body. Each spermatogonial cell divides mitoticaly and equally to form 2 primary spermatocyres and then these undergo unequal cytoplasmic division of Mitosis to form 2 spermatids and 2 Polar bodies. According to some investigators, polar bodies get disappeared. So haploid male gives rise to haploid gametes and diploid makes diploid gametes. Kindly read following references for details, http://www.mendeley.com/research/spermatogenesis-diploid-males-formicine-ant-lasius-sakagamii-3/ http://www.jstor.org/stable/20022189?seq=1 Senior Education Officer, BNHS, India. www.bnhs.org
Bitter Truth! Who says reason for world war IV will be Petrol? Reason lies in two words "Me and Mine".
Re:
Though inbreeding may be a cause of haploid male ants in some genera (citation? I haven't heard this before), many haploid male ants are the result of alternating generations. Haploid males mate with the diploid female queens, which then birth many sterile females and the occasional diploid female capable of parthenogenesis. Only unmated parthenogenetic females are capable of birthing males. Please elaborate on "polar bodies get disappeared." Please read: http://books.google.co.uk/books?id=dk2d ... ts&f=false http://en.wikipedia.org/wiki/Haplodiplo ... ion_system : "An offspring formed from the union of a sperm and an egg develops as a female, and an unfertilized egg develops as a male. This means that the males have half the number of chromosomes that a female has, and are haploid." "Every cell is a triumph of natural selection." Carl Sagan
I haven't found any further reference on disappearing polar body in male. I need to search more on this.
Senior Education Officer, BNHS, India. www.bnhs.org
Bitter Truth! Who says reason for world war IV will be Petrol? Reason lies in two words "Me and Mine".
5 posts • Page 1 of 1
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