How does the respiratory center detect increased levels of carbon dioxide?

The correct response highlights the mechanism through which the respiratory center in the brain detects increased levels of carbon dioxide (CO2) in the body. This detection primarily occurs through the diffusion of CO2 into cerebrospinal fluid (CSF). When CO2 levels rise in the blood, it diffuses readily across the blood-brain barrier and into the CSF.

Once in the cerebral spinal fluid, CO2 reacts with water to form carbonic acid, which ionizes into hydrogen ions and bicarbonate. The increase in hydrogen ion concentration leads to a drop in pH, providing an important signal to the chemoreceptors located in the medulla oblongata of the brain. This response prompts the respiratory center to increase the rate and depth of breathing, facilitating greater expulsion of CO2 from the body and helping to restore normal levels.

The other options do not accurately describe the primary method of CO2 detection. Measuring oxygen levels is less directly linked to the respiratory control for CO2, while monitoring blood pressure is not primarily a method for CO2 detection, and the release of neurotransmitters does not directly relate to the sensory process used by the respiratory center for CO2 changes. Thus, through the diffusion of CO2 into cerebrospinal fluid