What are the different types of buffering system in the body?
If the pH of the body gets too low (below 7.4), a condition known as acidosis results. This can be very serious, because many of the chemical reactions that occur in the body, especially those involving proteins, are pH-dependent.
Ideally, the pH of the blood should be maintained at 7.4. If the pH drops below 6.8 or rises above 7.8, death may occur.
It is the kidneys that ultimately remove (from the body) H+ ions and other components of the pH buffers that build up in excess. Failure of the kidneys to perform this excretory function is known as metabolic acidosis.
Excretion by the kidneys is a relatively slow process, and may take too long to prevent acute acidosis resulting from a sudden decrease in pH (e.g., during exercise).
The lungs provide a faster way to help control the pH of the blood. Acidosis that results from failure of the lungs to eliminate CO2 as fast as it is produced is known as respiratory acidosis.
The concentrations of both buffer components in the blood (HCO3- and CO2) are very large, compared to the amount of H+ added to the blood during normal activities and moderate exercise.