If someone dropped you on the moon without an astronaut"s equipment, what would happen? You"d die, of course. The human body depends on its environment. This engaging four-volume set, written at the sixth- through eighth-grade reading level, examines our bodies" inseparable relationship with the environment. Each volume presents the parts of a particular body system and how they work, things that go wrong and how they"re treated, how the environment affects the particular body system and impacts our health, controversial environmental issues (where applicable), and changes individuals and groups are making to fix environmental problems and restore health.The circulatory system consists of the heart and miles of arteries and veins that distribute oxygen and nutrients to every cell in the body, helping them to grow and function properly; the respiratory system, which provides the necessary oxygen, works in unison. Yet air pollution, smoking, and industrial hazards can damage these sensitive systems. This volume covers how these dynamic systems work properly, how the environment impacts their operation, and how doctors and therapists work to maintain and treat them.