As blood CO2 levels drop, how does the pH of the blood change?

When blood CO2 levels decrease, the pH of the blood increases, indicating that the blood becomes more alkaline. This relationship is primarily due to the carbonic acid-bicarbonate buffer system in the body. CO2 in the blood combines with water to form carbonic acid, which can dissociate into bicarbonate and hydrogen ions. When CO2 levels drop, there is less carbonic acid present, leading to a decrease in hydrogen ion concentration. Since a lower concentration of hydrogen ions corresponds to a higher pH, the overall effect is an increase in pH when CO2 levels fall. This response is vital for maintaining acid-base balance in the body, ensuring that the physiological functions that depend on a stable pH can continue efficiently.