My undergrad offered a course in the science of making beer.
The two classes that I felt truly helped were
1. Comparative Anatomy: Kind of a cross between gross anatomy and embryology. Gives a really solid Latin foundation, you'll learn a decent bit of embryo and just enough anatomy that you won't be completely lost in Gross lab.
2. Immunology. My undergrad course basically covered the immuno portion of our Micro course in med school.
I didn't take Histo in undergrad--a lot of people said that med school was cake after taking histo in undergrad.
Undergrad Micro teaches you some bigger concepts that will help translate--but the reality is you're going to learn 1,000 bugs and their toxins and yada yada, and basic undergrad micro just isn't that in depth.
I took Cell Bio 100-400 in college. I think it covered 1/2 of the 1st test in Histo and maybe touched a little Biochem. Yeah, you need to understand DNA, RNA, protein yada yada. Your cell bio 100 hits that. You don't need it 3 more times.
I took Biochem 1 in undergrad--it gives you a bit of a foundation, but I don't think you're any worse off for having not had it.
I took animal physiology--which is actually VERY helpful. The thing is, I had covered physiology in about 10 different bio courses throughout college. I'm not sure you need a formal course. But, it would be the 3rd course I'd recommend.
Undergrad genetics is a waste IMHO. Most people learn how to do the Mendellian square in high school. And then all you really need to get through medical genetics is that + understanding X-linked. They're going to teach you about the genetics of fruit flies and spicy peppers and chickens combs. If you're a bio major--it's not that bad a class. But it isn't going to make a significant difference.