Which university?

Do you mean are Bristol and UCL worth applying to as universities, or is it worth you personally applying to Bristol and UCL?

I mean are my grades/subject combination good enough to apply to UCL and Bristol.

Firstly, I wouldn't forget Oxbridge because of those grades. Cambridge yes, but you've got an (admittedly small) chance for Oxford.

And yes, Bristol and UCL are definitely worth applying to. Your AS results are really good! Obviously it would have been better if you got an A in Maths, but I don't think Maths is of critical importance for Biology. I'm not an expert in either university, but I think you're probably a really decent candidate for them.

You've got nothing to lose (apart from money) with respect to the Maths remark. If you've got a high B, then it's virtually impossible for you to drop a grade with a remark because you would have to lose so many points for that to happen. The remark probably isn't going to change anything since there's not really a lot of subjectivity when it comes to Maths so it's unlikely the examiner marked you incorrectly, but there is a small chance that you could be marked up.

They are more than good enough. If your GCSEs are of a similar high standard, then the only reason they would reject you would be a bad personal statement (so get working on it).

The only thing I'd check is whether they require Chemistry (just checked, and no).

I mean are my grades/subject combination good enough to apply to UCL and Bristol.

They are more than good enough. If your GCSEs are of a similar high standard, then the only reason they would reject you would be a bad personal statement (so get working on it).

The only thing I'd check is whether they require Chemistry (just checked, and no).

Yes. They're definitely good enough and a fine combination.

These are things I've thought of including in my personal statement. Please do tell if these are worth including or not.

-Work experience in Specsavers (don't know if this is relevant)
-Books read such as 'Introducing genetics-Steve Jones', 'Origins Human Evolution-Douglas Palmer'.
-Field trip-mathematical skills like collecting and manipulating data
-Currently working as a volunteer in a national trust site where I do gardening (which I can link with conservation)
-A 2 day trip to Oxford university where a medical student set us a problem to solve. (just for the record do I have to write down the question). It was something on the lines of how we could go about proving yoghurt can improve our digestive system/health.
-undertaken a 1 day programme in Thinktank about Forensic science. (where I had to conduct a variety of scientific experiments).

That's basically it.

shall I take 4 subjects at A2 level.

Specsavers is certainly irrelevant if it's just work experience (if it's a long term weekend job, it could be worth a sentence, I suppose). The books are great things to talk about - don't just list them, say something about them; what did you get from them? National Trust is somewhat irrelevant. The various trips you've been on seem relevant, but again make sure you say something more about them than just 'I went on this trip'.

I'm really paranoid. You sure? And shall I take 4 subjects at A2 level.

Yes I'm sure, combined with a strong PS you should be absolutely fine. In your position I would take 3 and try to do as well as possible. Taking four subjects, although conceivably resulting in having four top grades, is obviously much more difficult than taking 3. It's Bristol or UCL you're looking at, I'd stick with three, you're not in a position where you need to take risks.

Would you think I'm worthy for Oxford or Cambridge? Or is that too far fetched?

What else shall I do? Would watching a science show/lecture of some sort be relevant? I really don't know what to include (any tips if you have any). I need something that's quick and simple but biology related that I can quickly do in the last remaining weeks of the holiday because after I just want to focus on A2.