How do we breathe?
When you breathe in, or inhale, your diaphragm contracts and moves downward. This increases the space in your chest cavity, and your lungs expand into it. The muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale.
Where do we get the air we breathe?
We get oxygen by breathing in fresh air, and we remove carbon dioxide from the body by breathing out stale air. But how does the breathing mechanism work? Air flows in via our mouth or nose. The air then follows the windpipe, which splits first into two bronchi: one for each lung.