That's what pre-reqs are for. I'm sure if you got good grades in O-chem, Biochem, Calc, etc you'll be fine. And that's also what the admissions process is for, to weed out those students who might not be ready yet for a program such as this. If you have not had any medical experience previously, there might be some students that have had experience who seem to just get things.. but this should even out by the time the program finishes.
It seems that the retention rate of students who graduate is extrememly high for most AA programs. If you need extra help, I'm sure it'll be available.
