User148
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the question is 1a: https://pmt.physicsandmathstutor.com...0Variation.pdf

So I said 46 46 then 23 23 23 23 because I assumed that the cell first replicated its DNA to get 92 then division 1 gave 46 then division 2 gave 23.

but the mark scheme says all of the circles are 23: https://pmt.physicsandmathstutor.com...ation%20MS.pdf

So i'm assuming that the cells are in tension? I think this applies to female gametes only but i cant think of any other explanation.

thanks!
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Wannabevetnurse
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meiosis starts with diploid, so in humans 46, and after the 2 divisions it is haploid, so it starts with 4n then into 2n and 2n, then into 2n, 2n, 2n,2n
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User148
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(Original post by Wannabevetnurse)
meiosis starts with diploid, so in humans 46, and after the 2 divisions it is haploid, so it starts with 4n then into 2n and 2n, then into 2n, 2n, 2n,2n
Hi! Thanks for the reply!

Wouldn't 4n be 92? Then 2n would be 46 and n would be 23. However, here it's saying that 2n is 23.
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Wannabevetnurse
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Not really

2n is equal to 46 chromosomes, so 23 chromosome pairs.
4n is equal to 46 chromosome pairs. In biology we always look at it in chromosome pairs, never individual chromosomes
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