Non-trad student here. I'm trying to decide whether to retake freshman biology. I took a three semester intro sequence at my undergraduate institution (all with labs; Spring 2005, Fall 2006, and Spring 2007, B, A-, A respectively). If the courses were more recent I probably wouldn't consider retaking, but from what I can tell many medical schools require science prereqs to have been taken more recently than this, not to mention that fact that I'll have to relearn all this material anyways. Should I just retake the oldest one with the worst grade? Also in the picture is that, If I have to retake two semesters (which would be next summer) it also may delay my application for another year. Any advice would be greatly appreciated.