I start out with 2N (46). Then after meiosis I, I have two cells. Each cell has N (23) chromosomes. After meiosis II, I'm supposed to have N chromosomes again. But if the cells split up, won't N = 23/2?
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You have 2N (46) in the beginning, all in non-replicated form. Then in the S phase of interphase before meiosis 1, the DNA content is replicated.
So, at the anaphase 1, the homologous chromosomes"" are pulled at the ends, which makes 2 cells with half the chromosomes i.e. Haploid (N) with 23 chromosomes. But, this is not enough, because replication of S phase before meiosis 1 made sister chromatids on a chromosomes and anaphase 1 pulled homologous chromosomes and not the sister chromatids.
So, at the end of meiosis 1, you have 23 chromosomes in replicated form (this also tells why there is not S phase before meiosis 2).... So just like mitosis, meiosis 2 seperates the sister chromatids and you get 4 cells with haploid number in non-replicated form.
So, at the anaphase 1, the homologous chromosomes"" are pulled at the ends, which makes 2 cells with half the chromosomes i.e. Haploid (N) with 23 chromosomes. But, this is not enough, because replication of S phase before meiosis 1 made sister chromatids on a chromosomes and anaphase 1 pulled homologous chromosomes and not the sister chromatids.
So, at the end of meiosis 1, you have 23 chromosomes in replicated form (this also tells why there is not S phase before meiosis 2).... So just like mitosis, meiosis 2 seperates the sister chromatids and you get 4 cells with haploid number in non-replicated form.
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because N stands for the number of different kind of chromosomes at that stage, and the definition of a chromosome somehow can be related to either 1 or 2 chromotids
(chromosomes are more a measure of how many kinds of data than the actual quantity)
(chromosomes are more a measure of how many kinds of data than the actual quantity)