5 credits!? ouch thats nearly two normal years of bio, right?(atleast thats how the credits r at my school) but if your school gives/accepts online course that would be the best, if u can get 5 credits in.
ok, at my school u get 1 credit for a class for 1 trimester. so did u fail or just didnt have the right classes? if u didnt have the right classes they may let u test into it