Answer
The bicarbonate ion HCO3- is part of the bicarbonic acid (H2C03) bicarbonate buffer system. Carbonic acid is a weak acid and bicarbonate acts as the weak base of the system. Acids constanly enter the body fluids from such substances as lactic acid, phosphoric acid, carbonic acid, ketone bodies and sulfuric acid derived from food and respiration. Some of these acids are strong acids and readily dissociate to contribute hydrogen ions to the fluid environment. The consequent increase in the hydrogen ion content of the fluid disrupts the homeostatic balance by lowering the pH. The bicarbonate ion is an acceptor of H+ ions and removes them from solution, thus lowering their concentration and raising pH back to homeostatic values (7.35-7.45) ,
Work Step by Step
The carbonic acid bicarbonate acid buffer system is one of the chemical buffering systems by which the body regulates hydrogen ion concentrations in body fluids and thus maintains the proper homeosatic pH levels necessary for the optimal functioning of the bodies biochemical and physiologic processes. The phosphate buffer system, the serum protein buffer system as well as activities of the respiratory system and the renal system also help to maintain proper body hydrogen ion concentration and pH.
