How did you figure out the breakdown of your subject grade? I wanted to find out as well...
And someone from last year applied to get her papers re-checked for Bio. Her grade didn't change.
You figure out your subject grade breakdown by contacting your IBC. Component scores have already been released to them.
For bio a remark may not be worth it because bio is not very subjective and the examiners follows a markscheme that tells you what specifically to awards marks for for every written response question. Paper 1 can't be remarked because it's a MCQ paper, and your IAs can't be remarked either. The only things that can be remarked are papers 2 and 3.
To the OP: Have you looked at the boundaries yet? If you're one or two marks away I suggest remarking since English is subjective. If you're further than that, then I think it's risky and it's best if you just accept what you have right now.