The breathing process is controlled by:
- the diaphragm.
- rib muscles.
The diaphragm is a major muscle involved in the breathing process, and the rib muscles (intercostal muscles) also play a role in expanding and contracting the chest cavity during inhalation and exhalation. The pharynx is part of the airway but does not control breathing, and while blood vessels are involved in the transport of gases, they do not directly control the breathing process itself.