Learn all about the endocrine system with new, precise, yet easy-to-understand, definitions and explanations. What is the function of the endocrine system? What are the major glands and their functions? What happens if the endocrine system is not working properly? The answers to all of these questions are covered in depth with detailed graphics, diagrams and exciting video. On-screen, multiple-choice reviews at the end of each segment reinforce important concepts and make learning fun.