I only took Gen Bio I&II and did absolutely fine on the Bio section (Kaplan too)
The ORG portion of the exam covers ORG I&II. Depends on how studious you are.. If you take the exam w/o ORRG II, but study it from a few sources, you might get away w/ it.. Depends on you though. Personally, I wouldn't do that because doing well on the DATs is pretty darn important and you want to be as prepared as possible for them.
Best if luck