Did you know that about 18.5 percent of a human body's mass is carbon? All life on Earth depends on carbon. How carbon is taking in and given off through animals' breathing, the burning of fossil fuels, and more can be shown in the model known as the carbon cycle. In this informative and interesting book, readers will discover how the carbon cycle works. Designed to appeal to struggling readers, helpful diagrams are provided to clarify complex concepts and fascinating fact boxes add interest to the text.