And so the fourth phase of mitosis is anaphase. Anaphase is also kind of easy to remember because you can think that the 'a' in anaphase is for the 'a' in the word apart. So, during anaphase, the sister chromatids are going to get pulled apart towards opposite ends of the cell, essentially starting to separate the DNA so that each daughter cell can get their own copy of the DNA. During anaphase, some parts of the mitotic spindle are going to shorten in order to pull chromatids apart from each other. In other scenarios, the mitotic spindle will lengthen, and when the mitotic spindle lengthens, that's actually going to stretch the cell allowing the cell to start to divide.

If we take a look at our image below, we are showing you all of the phases of mitosis and already in our previous lesson videos, we've covered prophase, prometaphase, and metaphase as well. Here in this video, we're focusing on the fourth phase, anaphase, which the image for anaphase is over here on the far right. The events of anaphase are here in the middle. Of course, when you're thinking about anaphase, you think about how the 'a' in anaphase represents the 'a' in the word apart. The sister chromatids are going to get pulled apart from one another.

Notice here that, in metaphase, the chromosomes, which are replicated chromosomes, are aligned here in the middle on the metaphase plate. During anaphase, notice that the sister chromatids are getting pulled apart from one another. You can see that these sister chromatids are getting pulled in opposite directions.

The sister chromatids are getting pulled apart from one another. But notice that other parts of the mitotic spindle are actually lengthening, these parts that are lengthening, getting longer, they're actually pushing the cell and stretching the cell out. That is going to essentially facilitate the division of the cell as well. This here concludes our introduction to anaphase and how the sister chromatids get pulled apart. In our final phase of mitosis, we'll talk about telophase in our next video.

So I'll see you all there.