Oxyntic cells are large and most numerous on the side walls of the gastric gland. They secrete hydrochloric acid and castle intrinsic factor. Hydrochloric acid maintains a strongly acidic pH of about 1.5−2.5 in stomach and converts pepsinogen and prorennin in pepsin and rennin respectively. The chief cells or peptide cells are usually basal in location and secrete gastric digestive enzymes as proenzymes or zymogens pepsinogen and prorennin. Mucous cells (goblet cells) are present throughout the surface epithelium of gastric gland and secrete mucous. The major and minor salivary glands secrete a fluid saliva. Saliva is slightly acidic (pH 6.8).