Anatomy is like any other anatomy course. Lots of information in very little time. Your upperclassmen will give you lots of suggestions for physio. Go to office hours with Gilson and she will explain everything until you understand it.
I only took the basic prereqs for pod school. Looking back, I think it would have helped in terms of difficulty in the first year classes had I taken anatomy, physio, biochem etc. Regardless, my GPA would have been likely the same.
It may help a bit to take classes like Anatomy, Physio and Biochem in undergrad. Any prior exposure is helpful. That said, I took only the bare requirements and have a pretty good GPA. Plenty of people who took those courses struggled, so while it's helpful I don't think it's necessary by any means. As far as Anatomy is concerned, the level of detail you'll be going into far exceeds the rigor of whatever you learned in undergrad anyways.