Role and function of duodenum

The duodenum has many small villi, which can secrete digestive juice

, including bicarbonate and mucus.

2

. Neutralize gastric acid

into the duodenum. Food contains a lot of gastric acid, and the acidity of gastric acid is high. Bicarbonates secreted by duodenum can be neutralized with hydrochloric acid in gastric acid, thus protecting the small intestine from excessive acid stimulation.

3. Absorption of nutrients. The

villi on the duodenum wall are rich in microvilli, which increase the surface area and promote absorption. In duodenum, carbohydrates, proteins and fats are absorbed by villi cells and enter the blood circulation system.