Question

This hormone is secreted in the gastro-intestinal tract. It is a peptide hormone. It acts on the exocrine pancreas and stimulates secretion of water and bicarbonate ions. Identify the hormone.

• A. Gastrin
• B. Secretin
• C. Cholecystokinin
• D. Gastric inhibitory peptide

Answer 1

The correct option is B Secretin

Endocrine cells present in different parts of the gastro-intestinal tract secrete four major peptide hormones - gastrin, secretin, cholecystokinin (CCK) and gastric inhibitory peptide (GIP).

Secretin acts on the exocrine pancreas and stimulates secretion of water and bicarbonate ions. CCK acts on both pancreas and gall bladder and stimulates the secretion of pancreatic enzymes and bile juice, respectively. GIP inhibits gastric secretion and motility. Gastrin acts on the gastric glands and stimulates the secretion of hydrochloric acid and pepsinogen.