The gastric glands of the stomach secrete gastric juice. It contains hydrochloric acid, proenzymes- pepsinogen and prorenin. Hydrochloric acid maintains a strongly acidic pH of about 1.5 to 2.5 in the stomach. HCl kills bacteria and other harmful organisms that may be present along with food. HCl converts pepsinogen and prorennin into pepsin and rennin respectively.