Classes for 2015 MCAT

I'm planning my curriculum until I take my MCAT after Summer 2015 (by which time I'll have just finished my second year of college).
By that time, these are the classes I've planned to take.

Bio I/II
Molecular Bio I/II
Orgo I/II
Chem I/II
Physics I/II
Psych
Sociology
Social Psych
Biochem I
Microbio

I had 4 questions:

1. Will these classes leave me sufficiently prepared for the MCAT (not including the studying I'll be doing in the summer)? Is it alright that I won't have taken genetics or physiology - 2 classes I understand can help MCAT scores?

2. Would it benefit me to take Physiology or Genetics (or both) in the summer semester - while I'm studying for the MCAT? I always planned to dedicate my entire summer break to study for the MCAT, uninterrupted by school or work, but I'd fit a class or two in if it would help my score. Or, alternatively, would it be better to swap out Microbiology or social psychology with Physiology/Genetics?

3. I'll have finished my second year of college by the Summer 2015. If I take the MCAT after that, and graduate within 4 years, will my MCAT scores still be valid by the time I'm applying?

4. Would it be better to take Biochem II or Molecular Biology II? Are both necessary