Most universities don't seem to have specific subject requirements for Law, so your subjects are fine. I don't think biology would offer an advantage over english language, but if you were considering any other subjects, you could potentially swap one for maths, or do a language as some courses offer a year abroad. This would also keep your options more open to other courses if you change your mind. However your chosen subjects, while not facilitating, are still probably good preparation for law.
If you do want to contact a uni, it is worth it; I used a contact form on Oxford University's website and they got back quickly. Most universities are happy to help.