I realize grades are important for getting into graduate school, but how much do they really indicate one's potential to be a professional scientist? If I were a "B" student, should I rethink my career path? I'm just feeling discouraged. I have no idea if I'll be able to succeed as a scientist or not. I mean, I think B's indicate enough intelligence to at least pursue graduate work, but I wonder if they mean I don't have the insight to ever do anything significant in my field. Especially since I'm in a very competitive field. Any thoughts?