Title: Small Intestine Location, Function, Length and Parts of the Small Intestine
Headings: Small intestine
Small intestine
Small intestine
Figure 1. Small intestine
Function of the Small Intestine
Digestion and Absorption of the Major Organic Nutrients in the Small Intestine
Absorption of Water
Absorption of Carbohydrates
Absorption of Vitamins
Absorption of Proteins
Figure 3. Digestion and Absorption of the Major Organic Nutrients in the Small Intestine
Absorption of Lipids
Absorption of Minerals
Absorption of Nucleic Acids
Intestinal Secretion
Regulation of Small Intestinal Secretions
Intestinal Motility
Parts of the small intestine
Duodenum
Figure 4. Duodenum
Jejunum
Ileum
Blood supply of the small intestine
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Content: Small Intestine Location, Function, Length and Parts of the Small Intestine
Small intestine
by Health Jade Team 13.1K views
Contents [ hide]
Small intestine
Function of the Small Intestine
Digestion and Absorption of the Major Organic Nutrients in the Small Intestine
Absorption of Water
Absorption of Carbohydrates
Absorption of Vitamins
Absorption of Proteins
Absorption of Lipids
Absorption of Minerals
Absorption of Nucleic Acids
Intestinal Secretion
Regulation of Small Intestinal Secretions
Intestinal Motility
Parts of the small intestine
Duodenum
Jejunum
Ileum
Blood supply of the small intestine
Small intestine
The small intestine is the longest part of the alimentary canal and it begins at the pyloric sphincter of the stomach, coils through the central and inferior part of the abdominal cavity, and eventually opens into the large intestine. The term small intestine refers not to its length but to its diameter—about 2.5 cm (1 in.). The small intestine is approximately 6 to 7 m long (range 3–7 m) with a narrowing diameter from beginning to end. The small intestine consists of the duodenum, the jejunum, and the ileum. The small intestine receives chyme from the stomach and secretions from the pancreas, liver, and gallbladder. It completes digestion of the nutrients in chyme, absorbs the products of digestion, and transports the residue to the large intestine. The small intestine the site of most enzymatic digestion and about 90 percent of all nutrients absorption and most of the rest occurs in the proximal portion of the large intestine. Its length alone provides a large surface area for digestion and absorption, and that area is further increased by circular folds, villi, and microvilli. Most digestive enzymes that operate within the small intestine are secreted not by the intestine, but by the pancreas. During digestion, the small intestine undergoes active segmentation movements, shuffling the chyme back and forth and thereby maximizing its contact with the nutrient-absorbing mucosa.