Hello!

HCl is produced by the parietal cells of the stomach. To begin with, water (H 2 O) and carbon dioxide (CO 2 ) combine within the parietal cell cytoplasm to produce carbonic acid (H 2 CO 3 ). An enzyme called carbonic anhydrase converts carbonic acid into its component ions a hydrogen ion (H + ) and a bicarbonate ion (HCO 3 – ).

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