Well first of all, you're a sophomore so don't panic. I'm a grad student, had an overall 3.2 and still managed to get in because I've had a spectacular experience. You gotta understand that Tulane puts alot of emphasis on character. There's no guarantee that even you pull your GPA up over a 3.6 that you will get in. That said, yes, you can get in. There are many success stories of people on the board that have gotten into schools, including Tulane, with a low GPA/good MCAT. Just focus on your coursework and don't crap a brick. If you failed a course, and it is required for your major, then yes, retake it. If it is a prereq for med school, yes, retake it. I would also recommend retaking biochem, physio, other MS-1 year courses again if you failed it, but only if you pull a B+ or higher on it. Otherwise, do not bother retaking non-required courses because you're expected to get really high marks, if not, it would hurt more than help. Genetics sounds like a required class, if you passed, I'd ask an advisor to retake it or not (i wouldnt but im not everyone).