Question

Peptic cells secrete____
A. HCl
B. Gastrin
C. Cholecystokinin
D. Pepsinogen

Answer 1

Hint: Peptic cells also known as zymogenic or chief cells are associated with the word pepsin. Pepsin is the active form of the inactive complex secreted by the Peptic cells. It is important for the digestion of protein. The acidic environment converts this enzyme to its active form.

Complete answer:
Peptic cells are known as chief cells or zymogenic cells. From the basic understanding of biology, the word peptic is linked with the term pepsin which is an enzyme that breaks down proteins to amino acids.
But we all know that the enzyme pepsin is not present in its active state in the body, rather the inactive form of pepsin which is pepsinogen is secreted by the cells of the stomach.
It is later activated to pepsin with the help of hydrochloric acid at a pH of 1-2.
HCl is secreted in the stomach by the parietal cells also known as the oxyntic cells. These cells are located in the middle part of the fundus. The amount of HCl secreted in the stomach is directly proportional to the number of parietal cells present.
Therefore, option (a) is incorrect.
Gastrin is secreted by the G-cells which have a neuroendocrine origin. These are responsible for the synthesis and production of gastrin. These cells are found in the pyloric antrum region of the stomach and certain parts of the duodenum and pancreas.
Therefore, option (b) is also incorrect.
Cholecystokinin is secreted by the I-cells in the small intestine. It is responsible for inducing contraction of the gallbladder and induces digestive enzyme production. It is released under the signal of neurons from the brain.
Therefore, option (c) is also incorrect.
Pepsinogen is secreted by the peptic cells which are also known as chief cells. Pepsin in the stomach is responsible for the digestion of proteins, which are there in the ingested food. Pepsinogen is an inactive zymogen which is activated using hydrochloric acid.
So, the correct answer is “Option D”.

Note:
Peptic cells secrete Pepsinogen which is the inactive form of Pepsin. Pepsinogen is composed of a single polypeptide chain with high molecular weight. This secretion is influenced by factors like cholinergic response of the vagus nerve and the amount of acid in the stomach.