Topic summary
Control of ventilation
The control of ventilation in higher vertebrates is the physiological process, and the set of related mechanisms, involved in the control of breathing, which is the movement of air into and out of the lungs. Ventilation facilitates respiration. Term respiration refers to the utilization of oxygen and balancing of carbon dioxide by the body as a whole, or by individual cells (in the case of cellular respiration).
The most important function of breathing is the supplying of oxygen to the body and balancing of the carbon dioxide levels. Under most conditions, the partial pressure of carbon dioxide (pCO2), or concentration of carbon dioxide in the bloodstream, controls the respiratory rate.
The peripheral chemoreceptors that detect changes in the levels of oxygen and carbon dioxide are located in the arterialaortic bodies and the carotid bodies. Central chemoreceptors are primarily sensitive to changes in the pH of the blood, (resulting from changes in the levels of carbon dioxide) and they are located on the medulla oblongata near to the medullary respiratory groups of the respiratory center. Information from the peripheral chemoreceptors is conveyed along nerves to the respiratory groups of the respiratory center. There are four respiratory groups, two in the medulla and two in the pons. The two groups in the pons are known as the pontine respiratory group.
- Dorsal respiratory group – in the medulla
- Ventral respiratory group – in the medulla
- Pneumotaxic center – various nuclei of the pons
- Apneustic center – nucleus of the pons
From the respiratory center, the muscles of respiration, in particular the diaphragm, are activated to cause air to move in and out of the lungs.