If I was to do a BTEC Level 3 Applied Science (either medicine or forensic route) would I be able to do a degree in Marine Biology or would I have to do A Levels?
Im doing the level 3 extended medcial science course and biology a2 and got offers from unis for the intergrated masters in marine biology so its possible. Only portsmouth requries you to have a C in as biology the rest dont care. But saying that having both puts you at an advantage.
Why don't you look at UCAS/university websites to see whether they accept the BTEC for Marine Biology?
The following Russell Group unis accept BTEC Applied Science for Marine Biology or similar:
Liverpool - BSc Marine Biology - D*DD
Southampton BSc Marine Biology (with foundation) - DDD
Exeter - BSc Conservation Biology and Ecology - DDD-DDM
Glasgow - BSc Marine & Freshwater Biology - DDM
After a quick look, it would seem you would have a lot more choice if you looked at a more general Biology degree as Marine Biology specifically is only offered at a limited number of universities