I graduated with a Biology degree, and from what I can tell, it should get you by. Look up all of the DAT sub topics for Biology and compare them to the topics covered in Cliff's to be sure. I think complementing it with Feralis Bio notes is a good thing too. If time permits, I would go further and find additional resources--perhaps Khanacademy. The Bio section is random from what I've heard. They'll spit out small detailed questions, such as knowing that the ovary is the fruit of an angiosperm. Obviously my feedback shouldn't be taken to heart as much as someone who has already taken the DAT, but I hope it helped in some way! Good luck!