The small intestine's job is to absorb about 90 percent of the nutrients we consume, according to InnerBody. The small intestine is about an inch wide and approximately 10 feet long and is folded along itself in the abdominal cavity. It is twice the length of the large intestine.
The small intestine processes about 2 gallons of food and secretions every day and is divided into three sections: the duodenum, the jejunum and the ileum. The small intestine is made up of four layers, just like every part of the gastrointestinal system. These four layers are the mucosa, the submucosa, muscularis and the serosa.