![]() I'm gonna draw all my cells again, this is taking me twice as long because I have to do itįor twice as many cells, so that's one cell there. And once again, this is analogous to what happens in anaphase in mitosis, so let me. And now we're ready to anaphase II, and you can imagine So it might go, it might be something like that. So let me just draw it all out like this. So there you go, and remember this right over here, where the two sister chromotids attached, those are our centromeres. I've been doing that in blue, so I'm gonna continue to do it in blue, that are pushing the centrosomes apart, but are also attaching to the chromosomes at the kinetochores. So then it had a little bit of pink on it. The shorter orange chromosome on this cell had the longer, the Let me, has a littleīit of the orange here, and then I had the And this had a little bit of orange in it. And actually, let me drawĪll the magenta ones now since I have my magenta color selected. So this magenta one, it'll line up here over here. ![]() And I have my now dense chromosomes lining up along the equator here. And I'm gonna do it twice, because I'm now dealing with two different cells. ![]() So our centrosomes have migrated to the poles. And actually all of meiosis II is very similar to what And you can just imagine, it's very similar to what Let me draw an arrow here so you can see that we are entering into another phase. So once again, very strong analogy, especially to frankly, So the centrosomes have replicated and they will start to migrate to opposite ends of the cell. Shorter orange chromosome just like that, so they have condensed, and you've actually, each of these cells now will have duplicate centrosomes. You have this chromosome, right over here, and it had a little orange section from the chromosomalĬrossover just like this, and then you have the Little bit of the magenta that was from the chromosomal crossover back in prophase I, and then you have thisĬharacter right over here that is shorter. Into their denser form, so it's gonna look like this, this, and this. So your nuclear envelope dissolves again, and your chromosomes once again condensing (mumbles) I guess you could say Your nuclear envelope dissolves again, so let me show a dissolving In prophase II, just like in prophase I, and just like in prophase in mitosis, and let me write the phases here, this is prophase II we're talking about, prophase II. So this is one of the cells right over here, and then this is the other cell right over here. To draw it properly, so let me draw it, so let me draw this one first. And in prophase II, now I'm dealing with two cells here, so in prophase II, and I'm gonna do it for both of the cells that I have after I finished meiosis I, so in prophase II, so let me. So you can imagine meiosis II starts with prophase II. But then we get into meiosis II, which will allow us toĬomplete all of meiosis. interphase II, which you could kind of view as a rest period. There can be a rest period where you have an interphase II, and that will depend on the type of cell and the species and all of that, but it is possible, so I'll actually put that over here. Went back into our interphase, "is there kind of a rest period "between our two phases of meiosis?" And the answer is, sometimes. And you might be wondering, "Well, hey, after mitosis, we Then, sister chromatids separate and move to the opposite poles of the cell.We had completed meiosis I, and now we're ready to go into meiosis II. Next, the chromosomes line up in the center of the cell.Then each chromosome moves to opposite poles and the cell divides. In meiosis, the homologous chromosomes line up in the center of the cell.The cell divides, producing two cells with 4 total chromosomes Then, sister chromatids separate and move to the opposite poles of the cell. In mitosis, the chromosomes line up in the center of the cell.These are replicated during the S phase (the DNA synthesis phase). In the example below the cell has 4 total chromosomes. Mitosis and Meiosis both occur in eukaryotic cells. ![]() Each loop of DNA moves to the opposite side of the cell and the cell splits in half. Note that bacterial cells have a single loop of DNA. \) shows a comparison of mitosis, meiosis, and binary fission.
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