Small intestine PP

There are three parts to the small intestine; the duodenum, the jejunum, and the ileum. In the small intestine, Carbohydrates are broken down into monosaccharides, Lipids are broken down into individual fatty acids, and Proteins are broken down into individual amino acids. All of these macronutrients are broken down into their simplest forms and absorbed through the walls of the small intestine, made up of simple columnar epithelial tissue. The Pyloric sphincter regulates passage of chyme into the small intestine, where chyme is the acidic fluid that passes from the stomach to the small intestine, consisting of gastric juices and partly digested food. The pyloric sphincter is a smooth muscle sphincter that regulates passage of contents through the stomach to the small intestine. When it is constricted: nothing passes, and when it is relaxed: allows small amounts of chyme to enter the small intestine. This is an important regulation because you pepsin is required to cleave proteins before they enter the small intestine, and will prevent the small intestine from being overwhelmed.