When we breathe, our bodies exchange gases with the environment in a process called breathing, or respiration. But why do we breathe? What organs do we use when we breathe? In this video, we explore how the respiratory system works. We learn about cellular breathing and the organs involved in the breathing process - lungs, alveoli, bronchi and diaphragm; what a gas exchange is; how our body controls breathing, and conditions that affect breathing. Finally, we'll talk about how to keep our respiratory system healthy.