I can only tell you about my experience. I did Biology, Chemistry and Maths at A-level and did quite well in all those. I think a biological science degree will always require Alevel biology but you can probably combine it with a whole load of other subjects. My biochemistry degree accepted other alevels like physics, chem, maths, history, geography, IT but did want me to have two sciences. I think it depends on the Univeristy as to the actual grades but most want three Alevels above a grade C. It also helps if you have additional work experience and I got some by going along to my local hospital and doing a few days in their labs!
I agree with Holly most universities want 2 science subjects at A level. So I would say probably C or above in science at GCSE so that you can do it at A level. Then again C or above at A level for biology and another science.
I’d say certainly C or above, just try your very best. When it comes to some things, experience is very good – if you can get short summer work in a company of interest, that’d pay off massively. Otherwise, aim high, don’t be afraid of aiming high and achieve well. If it helps, I actually missed my minimum offer but was very lucky to be accepted anyway. Students who are good at school may not be so good at university, and vice versa. I was not good at school, but did much better in the university environment!
Since I went to uni in Ireland where we do things pretty differently (like SEVEN subjects at our A-level and you get into Uni based on points from your exams only) I can’t really comment on what Uni’s here want. I did two Science subjects to A level, chemistry and biology (and then maths, English, irish, german and geography) which was the minimum required to do Science at uni in Ireland. I did well in my biology and okayish in chemistry. I was never a very high-grade student in school but I did try very hard to get good grades in my science subjects. Like Daz said, you might not be super at school but then could be awesome at uni….I was kinda like that :D. As soon as I was allowed to study the subjects I wanted to, I started getting good grades!
There are so many science courses you can do at Uni but if you’re not sure exactly what you want to do, choose one that lets you try out a load of disciplines. You’re bound to find something you like. When I did my course I really like ecology, zoology and physiology but loved microbiology even more! So that’s the one I chose to continue with!