ANATOMY

Detailed explanation-1: -Normally, an increased concentration of carbon dioxide is the strongest stimulus to breathe more deeply and more frequently. Conversely, when the carbon dioxide concentration in the blood is low, the brain decreases the frequency and depth of breaths.

Detailed explanation-2: -Feedback for CO2 involves the carotid body and receptors in the brainstem, central chemoreceptors. Small increases in CO2 produce large increases in breathing. Decreases in CO2 below normal can, in sleep and anesthesia, decrease breathing, even to apnea.

Detailed explanation-3: -The level of carbon dioxide (CO2) in our body is what controls your breathing. When carbon dioxide reaches a certain level, a signal is sent from the breathing center in your brain stem to the breathing muscles, which triggers an inhalation. Upon exhalation, we exhale carbon dioxide and a new breathing cycle starts.

Detailed explanation-4: -But where does the stimulus for the reflex come from? It comes from the respiratory centres called medulla oblongata and the pons which are located in the lower brainstem.

Detailed explanation-5: -The partial pressure of oxygen and carbon dioxide and the concentration of hydrogen ions are the chemical factors that regulate respiration.