This book (with free Online Edition) is full of detailed revision notes and clear diagrams for OCR 21st Century GCSE Biology. It's designed to make revision straightforward - each section is split into a topic per page, with questions at the end to check what you've learned. Everything's explained simply and thoroughly with plenty of exam tips and guidance on 'Ideas about Science' and the Controlled Assessment. What's more, a free Online Edition of the whole book is included - perfect for revising on a PC, Mac or tablet device.