I was a biology major & chem/psych minor, but neither micro or biochem was required for my degree so I decided to wait and maybe take them post-bac. The only reason being that I was on scholarship at a really expensive school and I wanted to take advantage of more unique upper level classes I probably wouldn't find anywhere else (Biology of Aging- I'm interested in geriatrics, Uniqueness of the Human Brain, Health Economics- Pharmaceutical and Insurance Industry, etc).
Micro and biochem are only required for one school I applied to- Palm Beach Atlantic... but I wanted to apply there- so I am taking micro now and biochem over the summer. I have to say that we haven't really learned anything unique in micro (yet) that wasn't covered in other bio classes, but it is interesting and a good cumulative review. I think biochem will be really helpful even if I get into a school that doesn't require it though.
I would say definitely take them because they get to the core of the basic info you will need to know... for the PCAT as well, if you haven't already taken it.