The air we breathe contains oxygen, which is exchanged for a waste gas called carbon dioxide once your cells receive oxygen. Your bloodstream carries carbon dioxide back to the lungs where it exhaled, removed from your blood stream. This process is called gas exchange.
Besides gas exchange, our respiratory system also performs other roles, including:
- Regulating the temperature of the air, and moisturizing it to reach proper humidity level
- Filtering the air and protecting your body from harmful substances through coughing, sneezing, or swallowing
- Supporting your sense of smell