What are the parts of the small intestine?

The small intestine consists of duodenum, jejunum and ileum.

1. Duodenal

duodenum is the initial segment of the small intestine, about 25 cm long. The upper end is connected to the pylorus of the stomach, and the lower end continues to be jejunum through the duodenojejunal curve.

2. Jejunal

jejunum starts from duodenojejunal curve, and there is no obvious boundary with ileum, about 20-25 cm long. There are many circular folds on the jejunal mucosa, and there are a large number of small intestinal villi on the folds, which can greatly increase the contact area with food, thus improving the absorption rate.

3. The

upper end of ileum is connected to jejunum, and the lower end is connected to caecum, about 20-25 cm long. There are also circular folds and features on it, which is also one of the important places for food digestion and absorption.