Question

Which of the following is the correct set of glands that secrete zymogens :

• A. Pepsinogen – Chief cells of gastric glands
• B. Trypsinogen – Salivary glands
• C. Pepsinogen – Oxyntic cells of gastric glands.
• D. Chymotrypsinogen – Brunner’s glands

Answer 1

The correct option is A

Pepsinogen – Chief cells of gastric glands

The correct option is : A

Explanation of the correct option:

1. Zymogen is an inactive substance which is converted into an enzyme when activated by another enzyme, i,e. it acts as a precursor
2. Gastric chief cells secrete pepsinogen, i.e. an inactive zymogen protein .
3. A pepsinogen is an inactive precursor of the pepsin and is a proteolytic enzyme in the gastric juice.
4. Pepsinogen is inactive without the presence of HCl.
5. The pepsinogen in the presence of gastric acid, gets activated and is released in the form of pepsin.
6. Pepsin helps in the breakdown of the proteins.

Explanation of the incorrect option:

Option B:

Trypsinogen is the enzyme produced by pancreas and released into the small intestine. Whereas salivary glands secrete chloride and sodium secreting saliva.

Option C:

Pepsinogen is produced by chief cell not oxyntic cell, whereas the oxyntic cell helps to produce HCl in stomach.

Option D:

Chymotrypsin is produced by acinar cell of pancreas, whereas Brunner's glands secrete mucin in duodenum.

Final answer: Pepsinogen – Chief cells of gastric glands is the correct set of glands that secrete zymogens.