Our assignments for natural world usually combine some reading and some type of activity, but all the short video clips available online are a great resource, so I’ve been adding them to the studyguides as I find them.
The above two-minute, cell division video is a great example. Mitosis is a process, so it makes a lot of sense showing it as an animation, rather than discrete pictures in a figure. The video makes deciphering what’s going on in the diagram in the textbook a whole lot easier to understand, while the textbook diagram fills in the detail so the whole thing makes more sense.
There are also a number of useful interactive animations online. John Kyrk’s is quite nice. I like how the CellsAlive animal cell mitosis page lets you step through each frame in the animation.
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Wikipedia, as is so often the case, also has some nice images.