Well, where did you graduate from, whats you GPA.  You can get into good school for masters for anything with bio if you have taken some sort of courses on we you want to major in. But if you're thinking of getting into Harvard, well you betta spank the GRE and have some stellar recommendations, but still need to have some decent GPA.
I mentioned about the place you graduated from coz of connections of prof with the other schools. I have a friend who got into Cornell because the prof. knew the dean of the other school (recomm) -- but you still need to have some backing with that. He did have some spanking scores.