Most U.S. schools ask for 8 credits (one whole year) in each of: general chem, organic chem, genral biology, physics. This is more than enough for the MCAT.
As for your past courses: the only subject that is perhaps lacking is physics. I took this exam myself with precisely zero background in physics. I attest first-hand that even though I gained admission to medical school on my first attempt in the U.S., the physical science section was my lowest score - and my chemistry was pretty strong. Bottom line: you want to maximize your score, so give yourself the best chance, and be prepared.
Biochemistry is not really any help on this exam, in my humble opinion. Although physiology, genetics, and molecular biology are not required either, they will most definitely help you on the biology section. I used to teach MCAT prep. for a professional company and I submit to you that this test has become rather molecular in nature - more so than before. This probably reflects the wide-spread use of molecular diagnostics in modern medicine. The AAMC (the MCAT writers) are pretty up-to-date in that regard. Keep in mind that good test-takers and fast readers do infinitely better on this exam than folks who simply 'have a lot of knowledge'. Again, this was my observation as a student of the exam and later as a teacher.
The physics that you'll need to know for the MCAT is not calculus-based. You will need to know Newtonian mechanics, fluid dynamics, energy and translational motion (including angular motion), energy conservation, waves, sound, electromagnetism, electrostatics, circuits, work, momentum, optics, and atomic physics. Check out your your old course syllabus and see if you covered all of this. If you are applying to U.S. medical school schools, you're going to need 8 credits of physics, so I would just take it before the MCAT. If you are applying to one of several Canadian medical schools that does not ask for physics but one which has the MCAT requirement, take a professional MCAT prep. course and study dilligently. I'll bet you'll do well.
Any other questions? Just ask...
My best to you!
