Duodenum
Duodenum

Duodenum

The duodenum contains the same wall layers seen in the previous portions of the GI tract: mucosa, submucosa, and muscularis externa. The epithelia and lamina propria of the mucosal layer are thrown into villi. Especially notable in this image are the Brunner's glands in the submucosa. These glands are unique to the duodenum.