Within the parietal cells of the stomach, co2 and h2o are combined by to produce h2co3, which quickly dissociates into h+ and hco3-. h+ ions are pumped into the lumen of the stomach via a while hco3- is pumped into the blood in exchange for cl-, which ultimately enters into the lumen of the stomach as well.

Carbonic anhydrase, H+K+ATPase

Explanation:

Within the parietal cells of the stomach CO2 and H2O are combined by carbonic anhydrase to produce H2CO3,which quickly dissociates into H+ and HCO3- .H+ ions are pumped into the lumen of stomach via a H+K+ATPase,while HCO3- is pumped into the blood in exchange for Cl- ,which ultimately enters the lumen of the stomach as well.

i think the answer is terrae but not 100 percent sure. ▓▬▬ §

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a