This book is packed with practice questions on all the important topics in the current Higher Level AQA, Edexcel, OCR Gateway and OCR 21st Century GCSE Additional Science exams. The answers are included at the back of the book to help students to mark their own work, find out where they might be going wrong and improve their answers.. Matching study notes and explanations are also available in the CGP Revision Guide (9781841467566).