Final answer:
The bicarbonate buffer system is beneficial because it helps maintain blood pH at around 7.4, slightly outside its optimal range, allowing it to effectively neutralize acids and bases and adapt to environmental changes like high altitudes.
Step-by-step explanation:
The bicarbonate buffer system maintains a pH around 7.4 in human blood, which is slightly outside its optimal buffering capacity. This is advantageous because the system can better handle the daily acid-base fluctuations that occur in our bodies without a significant change in pH. The pKa of the bicarbonate buffer system is 6.37, which is close to the physiological pH, ensuring that the buffer can effectively neutralize both acids and bases.
The bicarbonate buffer system consists of carbonic acid (H₂CO₃), bicarbonate ion (HCO₃⁻), and carbon dioxide (CO₂). It works by either absorbing excess hydrogen ions (H+) or hydroxide ions (OH⁻), thereby preventing drastic fluctuations in pH. At the physiological temperature of 37°C, it's important to note that the actual concentration of H₂CO₃ is low, and it's primarily the CO₂/HCO₃⁻ equilibrium that plays a significant role in the buffering process.
Moreover, the presence of the bicarbonate buffer system enables humans to adapt to various environmental conditions, such as high altitudes, by adjusting the buffer to maintain the correct pH despite changes in the partial pressures of oxygen and carbon dioxide.