The breathing process is primarily controlled by the diaphragm and rib muscles, both actively involved in inhalation and exhalation. The brain stem regulates the rhythmic contractions of the diaphragm by monitoring carbon dioxide levels in the blood.
The breathing process is primarily controlled by the diaphragm and the rib muscles. These musculatures are responsible for the mechanics of air movement in and out of the lungs. The diaphragm is a large, dome-shaped muscle that contracts to increase the volume of the thoracic cavity and decrease intra-thoracic pressure, leading to inhalation. When the diaphragm relaxes, it allows the chest volume to decrease, which results in exhalation. Rib muscles, which include the intercostal muscles, assist in this process by moving the ribs to further change the volume of the thoracic space.
The brain stem plays a crucial role in regulating this process by monitoring the levels of carbon dioxide in the blood and sending nerve impulses to adjust the frequency and depth of diaphragm contractions. The pharynx is involved in the passage of air to the trachea but does not control the breathing process itself, and blood vessels are involved in the exchange of gases within the lungs but do not control breathing directly.