I think I had a question where I had to name the valves in the heart in order or something like that. It was a long time ago, so I don't really remember. I do remember having alot of developemental biology type questions, and only one or two biochem type questions, which dealt with oxidative phosphorylation. I also had a question that asked in some sneaky, obtuse way, which species had a notochord and not actual verterbrae. I definately don't remember what the answer to that one was.
I believe, despite what many people are saying to the contrary, that the kaplan book does a good job of preparing you for biology. Honestly, there is way too much material on the bio-section to just "cram." If its at all possible I would recomend taking a physiology class before you take the DATs because it will cover a wide range of topics in great detail.
As far as kaplan and the chemistry section is concerned; I feel like the kaplan book went way way way too much into detail in some areas and completely glossed over others. On the test I had a couple chemistry questions that I just scratched my head at and randomly picked whichever answer looked the least wrong.
But, anyways, really the only way to prepare for the bio section is to memorize as much as you possibly can. Alot of the questions are tricky and sneaky, and just having a cursory understanding of certain organs/pathways/species etc might not be enough. Whatever happens, I wish you good luck.