A few schools recommend non-science majors take advanced coursework in the sciences, particularly in biology. I don't know how much it affects your chances at admission, but at one interview I was asked why I didn't have any advanced science courses.
It was a closed file interview so he didn't see my (high) grades, so that might have been why he was asking me that question. (I actually had been taking an advanced biology course, but completely forgot about it.)