The buffer system that helps maintain a stable pH in human blood mainly involves carbonic acid, bicarbonate ion, and which gas?

1. Blood pH is kept remarkably stable by a chemical equilibrium involving a few closely related species. 2. The text states: "The buffer maintaining the pH of human blood involves carbonic acid (H2CO3), bicarbonate ion (HCO3–), and carbon dioxide (CO2)." 3. Oxygen, nitrogen, and hydrogen gas are not part of this particular buffering equilibrium described in the text. 4. So the blood buffer system specifically involves carbonic acid, bicarbonate ion, and carbon dioxide. _Source: OpenStax Biology Ch 2 "The Chemical Foundation of Life", p.52 §2.2 | Water_