Answer:
The proper maintenance of pH in the human body is important for the transportation and respiration process. The bicarbonate acts as the buffers for human blood.
The pH of the body depends on the concentration of carbon dioxide in the body. The presence of carbon dioxide decrease the body pH by increasing the hydrogen ion concentration in the blood. Arteries contains less carbon dioxide than venous blood and has high pH. This main difference is due to the amount of carbon dioxide.