Question

The hormone secretin is produced by-
A. Pancreas and influences the conversion of glycogen to glucose
B. Adrenal gland and accelerates heart beat
C. Testis and produces male secondary sex organs
D. Small intestine and stimulates pancreas

Answer 1

Hint: The hormone is extremely useful for proper functioning of liver and stomach as well. This hormone also controls the pH surrounding the duodenum and is responsible for neutralizing the pH for other digestive enzymes to come into function.

Complete answer:
Secretin is a peptide hormone produced inside duodenum. S cells in duodenum helps in secretion of Secretin.
The hormone is often released as a response to food.
This hormone stimulates the pancreas, stomach and liver.
Secretin is also released by neuron cells in the brain.
Pancreas releases bicarbonate from ‘ductal cells’ which is stimulated by secretion of secretion and hence it helps in maintaining the environment around duodenum.
Bicarbonate is a base and hence when it is released by the pancreas, it neutralizes the pH surrounding the intestine for other digestive enzymes to come into functioning.
Secretin is present in the form of ‘Prosecretin’ and its formation is stimulated by gastric acid.
Secretin is also involved in stimulating release of ‘bile juice’ from Liver. Bile juice further acts on fats and emulsifies them. Further, pancreatic lipase acts on those fats to digest them.
Secretin also acts upon parietal cells which are present in the stomach. They release gastric acid which might result in acidity. Secretin works upon parietal cells by stimulating the release of hormone somatostatin, further it regulates the acid releasing mechanism of parietal cells.
It is also used to test the functioning of pancreas.
Secretin is also known to be engineered by scientists as a cure for “autism”.
So, the correct answer is “Option D”.

Note:
Main function of Secretin is quite simple to understand. Everything starts from ‘Duodenum”. Duodenum is a part of the small intestine. When acid released by stomach reaches duodenum, this acid stimulates the release of ‘Secretin' by S cells present inside the duodenum and hence the name “Secretin”. Secretin release now results in release of HCO3 in the duodenum. This base now neutralizes the acid for other digestive enzymes to digest food.