The OCR AS Biology Revision Guide has been produced in partnership with OCR and is endorsed for use with the 2008 AS Biology specification. It provides comprehensive, specification-linked content, some of which is brand new and updated, so you can be sure you are covering everything you need to know for the exams. It is packed with engaging revision and practice material to keep you focused. It also contains a wealth of exam-style questions to test your knowledge and skills so you can fully prepare for the exams. This revision guide accompanies the free eBook which is available for every student from OCR when they register for the course.