My university has biochem (400-level) for biochem/chem majors and one for non-majors (200-level). Most bio majors took the 200-level. Also, our biochem was broken into 3 or 4 courses: general, metabolism and cellular respiration, DNA/RNA/protein/gene expression and analytical biochem if enough students (didn't get to take it). I say take the upper level one if you want a challenge and to prepare for medical school, but be sure to get a B or higher. At the university where I work, they have a 400 level watered-down biochem that is similar to my alma maters 200-level. Read the course description and inquire before you decide.