Question

Zymogen cells and chief cells that secrete?
A. Hydrochloric acid
B. Mucus
C. Pepsinogen
D. Trypsinogen

Answer 1

Hint: A cell that releases pepsinogen and chymosin in the stomach is known as the Gastric chief cell. Two different names of chief cells are zymogenic cells or peptic cells.Pepsinogen is generally activated into the digestive enzyme pepsin when it comes into contact with the acid produced by gastric parietal cells. Hence, pepsinogen is secreted by Zymogen cells and chief cells

Complete answer:
> Option (A) is Hydrochloric acid
Hydrochloric acid is the main constituent of gastric acid which is produced by the parietal cells in the gastric glands in the stomach. The secretion of this is complex and relatively an energetically expensive process.

> Option (B) is Mucus
Mucus is a normal, slippery and stringy fluid substance that is produced by many lining tissues in the body. It is essential for the body functioning and also it acts as a protective and moisturizing layer to keep the critical organs from drying out. Mucus usually acts as a trap for irritants such as dust, smoke, or bacteria.

> Option (C) Pepsinogen
Pepsinogen is a very powerful and abundant protein digestive enzyme that is secreted by the gastric chief cells as a proenzyme and then is converted by gastric acid in the gastric lumen to the active enzyme pepsin. In the 19th century, the role of pepsin and its precursor in protein digestion was first described.

> Option (D) is Trypsinogen
Trypsinogen is the precursor form of trypsin, which is a digestive enzyme. It is produced by the pancreas and found in the pancreatic juice, along with amylase, lipase, and chymotrypsinogen. It is cleaved to its active form, trypsin, by enteropeptidase, which is found in the intestinal mucosa.

Hence, The correct answer is option (C).

Note: The stimulation of a variety of factors including cholinergic activity from the vagus nerve and acidic condition in the stomach, chief cells release the zymogen (enzyme precursor) pepsinogen. Chief cells work in conjunction with the parietal cell that releases gastric acid, resulting in the conversion of pepsinogen into pepsin.