What is the Carbonic acid bicarbonate buffer system?

Hint :We know that the Human blood contains a buffer of carbonic acid $ {{H}_{2}}C{{O}_{3}} $ and bicarbonate anion $ (HC{{O}_{3-}}) $ in order to maintain this blood pH between $ 7.35\text{ }and\text{ }7.45 $ . In this buffer hydronium and bicarbonate anion are in equilibrium with carbonic acid.

Complete Step By Step Answer:
Carbonic acid is a weak acid which is in equilibrium with bicarbonate in solution. When significant amounts of carbonic acid and bicarbonate are present, a buffer is formed. - Metabolism produces more acids than bases and which is consistent with the body’s needs. The blood, with high base concentration is able to neutralize the metabolic acids.
While in the blood, bicarbonate ions serve to neutralize and are introduced into the blood through other metabolic processes. - In the body, there exists equilibrium between hydronium and oxygen which involves the binding ability of hemoglobin. An increase in hydronium causes the equilibrium to shift towards the oxygen and releases oxygen from hemoglobin molecules into the surrounding cells.
If a strong acid is introduced in the system, which is equivalent to having an increased concentration of hydronium ions, it will react with the bicarbonate anion and form carbonic acid, a weak acid. The equilibrium will thus shift to the left.

Note :
Remember that buffers are used often in biological research to maintain the pH of a specific process. This can be useful when the bacteria are culturing, and also their metabolic waste can affect the pH of their medium, consequently killing the sample. Many buffers have separate functions.