Summary:
- Inhaling is an active movement that results from the contraction of a muscle called the diaphragm.
- The rate of breathing is regulated by the brain stem.
- It monitors the level of carbon dioxide in the blood and triggers faster or slower breathing as needed to keep the level within a narrow range.
- The opposite events occur when the level is too low and the excess carbon dioxide is released into the air.
- The brain stem sends nerve impulses to the diafragm through the autonomic nervous system.