utv
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Is this correct? if reduction division Half's the number of chromosomes from the original cell. shouldn't this be the second division as I thought the second division causes the cell to have n number of chromosomes not the first?
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macpatgh-Sheldon
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Hi,

Halving of chromosome number occurs in Meiosis I, in which whole CHROMOSOMES migrate to the poles of the spindle (half the total number in the parent (sex) cell to each pole).

In Meiosis II, CHROMATIDS separate and move to the poles, SO IN THIS STAGE THE NUMBER REMAINS EQUAL TO ITS STARTING POINT = haploid.

Check out my short Powerpoint file attached - pics will make it easier to understand.

M (specialist biology tutor).
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utv
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this makes much more sense. thank you. so both in telophase 1 and the gametes produced have n number of chromosomes?
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macpatgh-Sheldon
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Firstly, thanks for the rep - so nice of you!

Yes, if you use 2n to refer to diploid no, then the gametes have n chromosomes. At telophase I stage, the nuclei have separated, BUT THE CYTOPLASM IS JUST BEGINNING to cleave into two, so the TWO SEPARATE NUCLEI have n chromosomes EACH, but of course, the whole cell is NOT YET 2 pro-gametes (to coin a term), BUT IS kinda one cell with two nuclei - CHECK OUT Slide No 6 in at-d file.
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utv
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thanks for your help sir😁
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