How does air get into the lungs?

How does air get into the lungs?

Richard Sheldon (Medical Advisor to the CA State Respiratory Care Board) gives expert video advice on: How is a pulmonologist different from other doctors?; What is the difference between the nasal cavity and the sinuses? and more...

The lung is pulled in by negative pressure. As the diaphragm contracts, it sucks the air in and it moves all the way out to the ends of the air passages through the bronchi and the bronchial's. What's important to know is that it's important to take periodic deep breaths to stretch everything out and get that air all the way out. And if you don't do it, then the body has a way of taking a deep sigh every once in a while. We really don't have control over that. We can do one ourself, but periodically the body kicks in with one just for our own benefit.