Hint: Our stomach has acidic enzymes working in it to dissolve the food. But our stomach lining does not get ruptured by this acidic medium. Different glands produce different enzymes to dissolve and degrade the food that reaches there. The acidic pH converts the inactive enzymes into the active ones.
Complete answer: What is gastric juice? A colourless fluid, thin and acidic, secreted in the stomach by the stomach glands to active enzymes to promote digestion. It is formed in the stomach lining. What are the chief cells? A chief cell/peptic cell/gastric cell/zymogenic cell is a gastric gland cell that releases pepsinogen and gastric lipase. These cells release the chymosin in ruminants.
They are present in the cardiac region of the stomach. > Option A: Isthmus of the gland- The isthmus has the dividing cells. They mature and move up to the surface cells. > Option B: Neck of the tubular gland- The neck has the immature stem cells which also on maturation move to the surface to replace the surface mucous cells. > Option C: Base of the tubular region- This region has various narrow tubules which are composed of zymogenic, parietal and mucous neck cells. There are zymogenic cells at the base which will produce enzyme pepsin and rennin.
Hence, The correct answer is option (C).
Note: The gastric juice is acidic to kill any bacteria that may have reached there. The pH in the stomach is 3.0 due to the presence of HCl and pepsin. Rugae are the special ingrowth in the stomach which help the stomach to expand after food consumption. The gastric juice contains Chymosin, lipases, pepsinogen, mucin, HCl and intrinsic factors.