What role does carbonic acid (h2co3) play in the human body?

The carbonic acid lowering the blood pH by breakdown into a bicarbonate, and proton ion. Carbonic anhydrase is known as an enzyme which helps to enable the breathing out CO2, and the balance the pH of the blood.

Bicarbonates are known as the intermediate in the transport of carbon dioxide out of the body by the process of respiratory gas exchange. Carbonic acid which is known as a weak acid forms 2 types of salts one is carbonates, and another is bicarbonates.

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emerging idea only occurs as a raw idea that could appear out of nowhere. meanwhile, to reach scientific consensus , that idea must be structured and tested over and over again through various experiments. the scientific consensus transforms the raw idea into idea that is more reliable through the process of scientific elimination.