Answer:
1. Increases output of enzymatic-rich pancreatic juice- cholecystokinin
2. Increases output of pancreatic juice rich in bicarbonate ions- secretin
3. : Increases HCl secretion and stimulates contraction of intestinal muscle- gastrin
4. : Stimulates insulin release and mildly inhibits HCl production-Gastric inhibitory peptide
Explanation:
1. Cholecystokinin is secreted by the duodenum of the small intestine and serves to stimulate the release of enzymes of the pancreas. In response to the presence of fatty acids and partially digested proteins in the duodenum, cholecystokinin triggers the release of pancreatic juice having enzymes and also stimulates the emptying of bile in duodenum.
2. The secretin hormone is also secreted by duodenum in response to the presence of acidic chyme in duodenum. The hormone triggers the release of sodium bicarbonate from the pancreas in pancreatic juice.
3. Hormone gastrin is released from the mucosa of the stomach in response to distension of the stomach by food and triggers gastric glands to secrete the enzyme pepsinogen and HCl. It also triggers contraction of lower esophageal sphincter and relaxes pyloric sphincter.
4. Gastric inhibitory peptide hormone is released from duodenum in response to the presence of glucose-rich partially digested food in the duodenum. The hormone stimulates the secretion of insulin from the pancreas.
