Question

To what chemical signal is the
body most sensitive with regard to respiratory control?

Answer 1

The body regulates the respiratory rate through chemoreceptors that primarily use CO₂ as a signal. Sensors in the blood vessels and brain send signals to adjust the respiratory rate in response to changes in CO₂ levels, and changes in CSF pH affect the respiratory center in the brain to modulate breathing rate.

Step-by-step explanation:

The body regulates the respiratory rate by the use of chemoreceptors, which primarily use CO₂ as a signal. Peripheral blood sensors are found in the walls of the aorta and carotid arteries. These sensors signal the brain to provide immediate adjustments to the respiratory rate if CO₂ levels rise or fall. Yet other sensors are found in the brain itself. Changes in the pH of CSF affect the respiratory center in the medulla oblongata, which can directly modulate breathing rate to bring the pH back into the normal range.