The circulatory system has an important job: delivering oxygen from the lungs to the cells and organs of the rest of the body, as well as remove waste products. The system is huge! The heart pumps blood constantly through 60,000 miles of blood vessels. In this informative book, readers explore the heart, blood, and blood vessels that make up the circulatory system. Full-color photographs as well as diagrams aid readers' understanding of how the system works. Information about disorders and diseases of the circulatory system, as well as tips on how to keep the system healthy give readers a real-life perspective on this important system in their body.