Which of the following controls secretion of bile from gall bladder?
Secretin
Gastrin
Somatostatin
Cholecystokinin
Secretin stimulates pancreas to release alkaline bicarbonate solution into duodenum to neutralise the acidic chyme.
Secretin acts in tendem with another hormone called Cholecystokinin. It not only stimulates pancreas but also stimulates gall bladder to release the bile.
Gastrin is secreted by g cells in response to presence of proteins etc . Gastrin stimulates the stomach to release hydrochloric acid.
Somatostatin stimulates stomach to stop releasing the hydrochloric acid when the need for maintaining acidic environment in stomach is over.
Hence option D is correct.