What is a small intestine?

The small intestine is a part of the digestive system that is responsible for the absorption of nutrients from food and the digestion of carbohydrates, proteins and fats. It is a long, thin tube that connects the stomach to the large intestine. The small intestine is made up of three sections: the duodenum, the jejunum and the ileum.

The duodenum is the first section of the small intestine and it is where most of the digestion takes place. It is here that the food from the stomach is mixed with enzymes from the pancreas and bile from the liver. The enzymes break down the carbohydrates, proteins and fats into smaller molecules that can be absorbed by the body. The bile helps to break down fats.

The jejunum is the middle section of the small intestine and it is here that most of the absorption of nutrients takes place. The walls of the jejunum are lined with villi, which are small, finger-like projections that increase the surface area of the intestine. The villi are covered in microvilli, which are even smaller projections that help to absorb nutrients.

The ileum is the final section of the small intestine and it is here that any remaining nutrients are absorbed. The ileum also absorbs water and electrolytes from food.

The small intestine is a vital organ for the absorption of nutrients and the digestion of food. Without the small intestine, the body would not be able to get the nutrients it needs to function properly.