The buffering effect of the blood

Human blood is a buffer system. After a rough estimate: the oxygen consumed per person per day to be approximately 600L (equivalent to 27mol oxygen), producing 480L carbon dioxide (equivalent to 32mol carbon dioxide), generates about 21mol carbonic acid, which is about equal to 2L concentrated hydrochloric acid. However, oxygen inhalation person to exhale Calcium lactate from the entire process, the blood pH is always maintained at 714 ± 0103 range, the change is minimal. This is in addition to the body's acid drainage function, which add a deep breath exclude CO2 and renal elimination of excess acid from the outside, should be attributed to the buffering effect of the blood.
Blood produced during the metabolism of non-volatile acids, such as lactic acid, pyruvic acid, also as a buffer. These substances are generally not in the alveoli in the urine, mainly by plasma bicarbonate buffer, such as the role of lactic acid generated carbonic acid into buffered lactic acid excreted via the alveoli. Blood alkaline substance has cushioning effect, which mainly comes from food. People eat vegetables and fruit, which contains sodium citrate, potassium phosphate, disodium hydrogen phosphate and sodium bicarbonate bases, their in vivo-generated base into the blood, the cause of the OH-concentration fluid. At this point depends mainly on the plasma bicarbonate --- carbonate, and also by hydrogen phosphate buffer and plasma proteins.