kaksteistsõrmiksoolega

Kaksteistsõrmiksool, also known as the duodenum, is the first section of the small intestine in humans and many other vertebrates. It originates from the pylorus of the stomach and extends to the jejunum. The name "duodenum" derives from the Latin word for "twelve," referring to its approximate length, which is about twelve finger-breadths.

The primary role of the duodenum is to act as a mixing chamber. Here, partially digested food, or chyme, from the stomach is mixed with digestive juices from the pancreas and liver. These juices contain enzymes essential for breaking down carbohydrates, proteins, and fats. Bile, produced by the liver and stored in the gallbladder, is also released into the duodenum to aid in fat digestion and absorption.

The walls of the duodenum contain specialized glands called Brunner's glands, which secrete alkaline mucus. This mucus neutralizes the acidic chyme entering from the stomach, protecting the intestinal lining from damage and creating an optimal environment for the digestive enzymes to function effectively. The duodenum also plays a role in regulating the rate at which food moves from the stomach into the rest of the small intestine. Hormones released in response to the presence of chyme and digestive juices help control gastric emptying.