The small intestines are located between the stomach and the large intestines

The small intestines are located between the stomach and the large intestines. Specifically, they start at the pyloric sphincter and end at the ileocaecal valve. They are narrow and long to allow digestion and absorption of food. The standard length of the small intestines in an adult human being is five meters but they may be shorter or longer. The three parts of the small intestines are the duodenum, jejunum, and ileum (Tortora and Grabowski 49). The majority of digestion and absorption of food takes place in the small intestines. Chemical digestion takes place in the small intestines where many enzymes that facilitate digestion are secreted. In the small intestines, proteins and peptides are digested into amino acids. Lipase enzymes are used to degrade fats into glycerol and fatty acids. Some carbohydrates are also digested in the stomach to form simple sugars. The process of absorption takes place where food nutrients are diffused into the bloodstream. The small intestines have many villi that have networks of capillaries to help indigestion. Monosaccharides, amino acids, water, iron, and many others are absorbed here.