I haven't taken Cell Bio, Genetics, Anatomy & Physiology, or Biochemistry yet. Would it be ok to self-study these topics? I am trying to avoid a gap year(s). I know Biochem is a must to take before MCAT but are Cell Bio, Genetics and A&P a must as well?
Biochem is a must but the others you mentioned are not needed. I never took cell bio and genetics (only took what was covered in my basic bio1/2 sequence) and never took A&P and I scored pretty high (520).
Definitely take biochem. You should also take A&P before med school. Not necessary for MCAT prep (but it wouldn't hurt either), but it'll help with your first year dissections. As I've heard a couple SNDers say: you can never over learn A&P.