Small intestine facts for kids

Small intestine
Diagram showing the small intestine and surrounding structures
Latin	Intestinum tenue
System	Digestive system
Artery	Superior mesenteric artery
Vein	Hepatic portal vein
Nerve	Celiac ganglia, vagus
Lymph	Intestinal lymph trunk

The small intestine is between the stomach and the large intestine. In humans over 5 years old, a small intestine may be five to six meters long. It is where most of the digestion and absorption happens.

The small intestine has three regions – the duodenum, jejunum, and ileum.

• The duodenum receives bile and juice from the pancreas. It is where most digestion takes place. Secretions neutralise the stomach acidity, and enzymes digest the food.

• The jejenum: the products of digestion (sugars, amino acids, and fatty acids) are absorbed into the bloodstream here.

• The ileum: absorbs vitamin B12 and bile salts and any products of digestion which were not absorbed by the jejunum.

Images for kids

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  Micrograph of the small intestine mucosa showing the intestinal villi and crypts of Lieberkühn.

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  Small intestine in situ, greater omentum folded upwards.

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  Second stage of development of the intestinal canal and peritoneum, seen from in front (diagrammatic). The liver has been removed and the two layers of the ventral mesogastrium (lesser omentum) have been cut. The vessels are represented in black and the peritoneum in the reddish tint.