small intestine: Quick Facts

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Oct. 30, 2026

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Soft robotic enteroscope offers a new approach to small intestine examination • Oct. 28, 2026, 11:02 PM ET (News-Medical)

Photos and Videos

Diagram showing the anatomy of the small intestine with labeled regions (duodenum, jejunum, ileum), a cross-section highlighting muscle and mucosa layers, an enlargement of mucosal folds (plicae circulares), and a detailed view of a villus structure with epithelial, goblet, endocrine, and Paneth cells, microvilli, blood capillaries, and lacteal.

Diagram of the human digestive system viewed from the front, showing and labeling organs including the mouth, teeth, tongue, salivary glands, pharynx, esophagus, liver, stomach, gallbladder, pancreas, large intestine, small intestine, appendix, rectum, and anus.

Detailed diagram showing the transport of lipoproteins in the human body, illustrating how dietary fats and cholesterol are absorbed in the small intestine, packaged into chylomicrons, and transported through lymphatic vessels and the bloodstream. The diagram traces the conversion of chylomicrons to VLDL, IDL, LDL, and HDL particles, highlighting their roles in fat and cholesterol delivery, storage, and recycling, with labeled pathways to the liver, muscle, and adipose tissue, and includes cellu

Is the mesentery a distinct organ?

The small and large intestines animated

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Topics

Lieberkühn’s glands jejunum ileocecal valve duodenum ileum Vater’s ampulla Brunner glands pancreatic duct duct of Santorini celiac disease large intestine

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