The Parietal cells are found to be round, large, or pyramidal in shape which have rounded nuclei at the center. These parietal cells secrete Hydrochloric Acid(HCl) which is one of the most important components of gastric acid, that activates the other enzymes. These cells are highly acidophilic, which means they stain pink color. These cells are found in the Fundic glands and the walls of the tubes.