You don't need to take anatomy, there are some very basic anatomy questions, but they won't ask what innervates what muscles or the names of the muscles and attachments. You can get all the info you need from the resources people use here.
Also, you could take it just to make dental school easier the first semester, but I don't think it's worth it unless you have a genuine interest in it. I went in totally blind along with pretty much all of my classmates and we made it out fine. I wouldn't recommend taking it in undergrad because it's traditionally a difficult class with a lot of weight and can be detrimental to your GPA, unless you ace it of course. I'd spend the time enjoying undergrad, volunteering, picking up an instrument, etc.