People have self-taught Biochem and they have been fine, so you should be OK teaching the metabolic pathways to yourself.
https://aamc-orange.global.ssl.fast...a-4c00-83dd-c17cee034c47/mcat2015-content.pdf
That's the content list per AAMC. It might be in your best interest to know the metabolic pathways inside and out as you may not want to run into any surprises on test day. IMO, more detail > not enough detail.
EDIT: refer to page 19 for list of metabolic pathways