What substance is considered a regulator of blood pH?

Carbon dioxide serves as a crucial regulator of blood pH through its role in the bicarbonate buffering system. When carbon dioxide is produced as a byproduct of cellular respiration, it diffuses into the blood where it can react with water to form carbonic acid. This reaction leads to a dynamic equilibrium that can shift based on changes in CO2 levels, affecting the concentration of hydrogen ions in the blood.

Increased carbon dioxide levels result in more carbonic acid formation, subsequently leading to a decrease in blood pH (making the blood more acidic). Conversely, when carbon dioxide levels drop, it reduces hydrogen ion concentration, increasing blood pH (making the blood more alkaline). Thus, the control of carbon dioxide levels in the blood is vital for maintaining acid-base homeostasis and regulating pH effectively.