Duodenum
Duodenum[edit]
The duodenum is the first section of the small intestine in most higher vertebrates, including humans. It is a hollow jointed tube connecting the stomach to the jejunum.
Anatomy[edit]
The duodenum is approximately 25–30 cm (10–12 inches) long and is shaped like a "C". It is divided into four parts:
- The superior part
- The descending part
- The horizontal part
- The ascending part
The duodenum is located in the upper abdomen and is mostly retroperitoneal, meaning it is located behind the peritoneum.
Histology[edit]
The duodenum has a unique histological structure that includes:
- Villi: Finger-like projections that increase the surface area for absorption.
- Microvilli: Microscopic projections on the surface of the villi.
- Brunner's glands: Located in the submucosa, these glands secrete an alkaline mucus that helps neutralize gastric acid.
Function[edit]
The primary function of the duodenum is to receive the chyme from the stomach and continue the process of digestion. It also plays a crucial role in:
- Neutralizing stomach acid
- Mixing chyme with digestive juices from the pancreas and bile from the liver
- Absorbing nutrients such as iron and calcium
Clinical Significance[edit]
The duodenum can be affected by various diseases and conditions, including:
- Duodenal ulcer: A common form of peptic ulcer disease.
- Celiac disease: An autoimmune disorder affecting the small intestine.
- Giardiasis: An infection caused by the parasite Giardia lamblia.
Development[edit]
The duodenum develops from the foregut and midgut during embryogenesis. It is initially a solid cord of cells that later becomes a hollow tube.
Related Pages[edit]
Gallery[edit]
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Diagram showing the position of the duodenum in the digestive system.
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Anatomy of the small intestine, including the duodenum.
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Illustration of the duodenum and its relation to surrounding organs.
