Some stomach cells transport chloride ions inside and bicarbonate ions outside the cell via a same transport protein. Such a transport mechanism is called a/an quzilet.

Such transport mechanism is called Antiport.

Explanation:

The production of hydrochloric acid (HCl) by the parietal cells requires the activity of the enzyme, carbonic anhydrase.In the presence of carbonic anhydrase  CO₂ and H₂O are converted  to HCO⁻   and H⁻.

The newly generated proton  (H+ )s transported into the lumen of the  stomach via the e H ₊₋K +ATPase (called the proton pump)Concurrently, HCO₃ ⁻  exits from the  basal surface (blood side) of the parietal cell via the HCO₃⁻   ₋ Cl antiporter.

The chloride ionneeded to form HCl, enters the parietal cell from the blood via the  HCO₃⁻₋Cl⁻ antiporter and exits at the luminal side by the Cl⁻ channel. Once within the lumen of the  stomach, cl⁻ combines with H⁺to form HCl.

The luminal K⁺ that is needed to maintain the activity of the proton pump(H⁺₋K⁻ATPase)enters the parietal cells from the stomach lumen by the H⁺₋K⁺ + ATPase and is then recycled back  into the lumen of the stomach by the K⁺ channel.