The human body requires oxygen to live. This oxygen is used by the body, which then expels carbon dioxide. As you sit in the chair, unconsciously your lungs pull in air about 30 times every minute, and push out carbon dioxide just as often. The diaphragm is a vital muscle that contributes to that mechanical activity as it pulls down the lungs which then expand taking in air. How do the lungs and diaphragm work together to compete this work?