Oxygen is one of the most essential needs for life on Earth, and respiration is how living things use it. But there's a lot more going on in this seemingly simple process than you might think. The respiratory system is in some ways the most underappreciated of the body systems, since it works 24/7, mostly without being noticed, and never gets a single moment's rest. In this book, readers discover the most fascinating facts about respiration, the structure of the lungs, and even some of the seemingly gross processes that happen in their body!