The body makes secretin when chyme enters the duodenum of the small intestines. Like others, secretin is made by special cells in the duodenum. As we have learned for some of the other hormones, secretin targets the stomach to make less enzymes and acid, and to make the mixing action slow down. More importantly, though, secretin also causes the liver to make more bile, while causing the pancreas to make bicarbonate ions. Bicarbonate ions are very important for the duodenum because in order for food to be broken down, the stomach has to make lots and lots of hydrochloric acid. The stomach secretes special mucous to help protect it from being damaged by this very acidic chyme while it is mixing and being processed in the stomach. But when the chyme leaves the stomach to go to the duodenum, it has to be made less acidic or it will damage the duodenum. Bicarbonate ions are said to buffer acids, or in other words, they make them be less acidic. Bicarbonate ions added to acidic chyme will make the chyme not be able to damage the duodenum. That is why the bicarbonate ions that are made because of secretin are so
The body makes secretin when chyme enters the duodenum of the small intestines. Like others, secretin is made by special cells in the duodenum. As we have learned for some of the other hormones, secretin targets the stomach to make less enzymes and acid, and to make the mixing action slow down. More importantly, though, secretin also causes the liver to make more bile, while causing the pancreas to make bicarbonate ions. Bicarbonate ions are very important for the duodenum because in order for food to be broken down, the stomach has to make lots and lots of hydrochloric acid. The stomach secretes special mucous to help protect it from being damaged by this very acidic chyme while it is mixing and being processed in the stomach. But when the chyme leaves the stomach to go to the duodenum, it has to be made less acidic or it will damage the duodenum. Bicarbonate ions are said to buffer acids, or in other words, they make them be less acidic. Bicarbonate ions added to acidic chyme will make the chyme not be able to damage the duodenum. That is why the bicarbonate ions that are made because of secretin are so