yea there's just soooooo much material covered in bio that if you're not on top of your game, you'll get lost in the sea of information and it'll get hard for you to figure out which areas are your weakness and that might get you on the actual exam. main thing is to know when going over everything, which areas are your weakness and make sure to go over that material over and over until it becomes ingrained. that's what really helped me do well in the Bio section. btw, as poster above stated, wikipedia is immensely helpful. anytime something is not clear, don't brush it off. Use wiki to clear up any doubts you have while reviewing. if you have any more questions feel free to ask =)