From your original post i got the impression that all things being equal you like the idea of Nottingham probably with birmingham as a second choice. If this isn't the case I am sorry. If it is then I would say you need to seriously consider what the chances of you getting an A in biology are if you think that it is unlikely then don't go for nottingham. However if nottingham is where you really want to go there is no harm in your putting Notts as your firm choice and then Brum as your insurance so if you miss the A in biology you still have a med school that you like to fall back on.