Medicine, is it worth applying

Ok, so Cambridge may have a reasonably low applicate to offers ratio when compared with other unis such as bristol or nottingham and the like however the applicants are of better quality.
Is it worth applying to medicine with gcse's 5a* 4a 2b 1c and if lucky i could get a 40+ points prediction on my IB but, heres the but, i am doing maths physics chemistry higher level and probably 99% of applicants have biology and chemistry in their fodder and i don't, so yeah, is it worth having a shot or am i dreaming. oh and does a physics olympiad thing count for anything even tho i don't take the exam till November way after the application deadline. oh and an extended essay in chemistry will surely help as well, but theres no biology for me, well there is in the form of a human bio chemistry option we do for the chemistry HL. So, is biology a must for all cambridge medics even though they say it isn't in the prospectus etc?