I posted this a while ago on another thread:
After a year of mostly Cs in general chemistry and biology, I started to doubt my ability to succeed as a bio major. I knew I had to make a change. I spent some time evaluating my situation and more importantly, my seemingly inabillity to do well in chemistry and biology classes. After much contemptation, I realized that I was not learning the concepts, instead I was merely memorizing them. This frank realization changed the way I studied. I started to place heavy emphasis on understanding the concepts, as well as the lectures. I prepared for every lecture, went to office hours, and most importantly, I concentrated on the important concepts. As I did this, my grades did not only slowly but steadily improved, but I was also spending less time studying for my classes. I didn't study harder than before, instead I studied smarter. For the last 3 years, I had a 3.68 GPA while averaging 20 units per quarter. I was granted interview to UCSD, UOP, Western, USC and UCSF. During my UCSF interview, the interviewer even told me it is perfectly understandable that some students struggled during their first year.
Take this opportunity to evaluate your situation and more importantly, learn why you didnt do well. Improvement indicates commitment, determination, and persistance; all qualities that the admissions committee look for in a candidate.