One of the best breaks you can take during hardcore MCAT study sessions, besides going out for some fresh air, is to test your knowledge through practice questions. You can't lose - if you answer correctly, all of your studying is validated; and if you get them wrong, you feel a renewed drive to hit the books.

Examkrackers offers a Daily MCAT Quiz on its website for registered users (registration is free). Each daily quiz consists of 3 passage-based questions, one from each of the sections covered on the MCAT: Biological Sciences, Physical Sciences, and Verbal Reasoning. After submitting each answer, you'll be able to see a detailed explanation for the question. And over time, your scores are tracked and compared to other students who have taken the quizzes.

So go ahead: register now and take the MCAT quizzes whenever you need a break from the books!