Explain the Chemical Control of Respiration

Let us now focus on the chemical control of respiration. But before that, let's get to know which chemicals are involved in this process. The main chemical factors which influence the respiratory centers are the tension of carbon dioxide and oxygen in blood. In the carotid body (a clump of large polyhedral cells richly supplied with the blood vessels and nerves situated near the carotid bifixcation on each side) and in the aortic bodies (cells in the walls of the arch of aorta), cells are sensitive to carbon dioxide lexcess (increased pCO₂) and oxygen lack (decreased pO₂). When carotid body and aortic, body are stimulated, impulses pass to the respiratory centre in the medulla, through the branches of vagus and glossopharyngeal nerves and stimulate respiration.

Figure illustrates the carotid and aortic bodies and the nerves.