Human Digestive Activity

The digestion process starts in the mouth where food enters and is moistened by saliva and then the teeth chew the food which transfers the food into bolus. When the bolus leaves the mouth, it is passed to the pharynx which is where it is swallowed, then moves into the esophagus which is what connects the pharynx to the stomach. When the bolus arrives in the stomach, acid mixes with the bolus to make it into chyme which is a semi liquid good mass. The food is only partially digested in the stomach and the chyme does not leave the stomach for 2 to 6 hours depending on the size and type of food that was eaten. Then the chyme is passed to the small intestine where most of the digestion and absorption of nutrients from the food take place. There are three parts that the small intestine is divided up to and they are known as the duodenum, the jejunem, and the ileum. Discharge of bile from the liver and gallbladder help out the digestion and absorption of fat. All of the materials that are not absorbed in the small intestine move on to the large intestine through a sphincter which keep the material from going back into the small intestine. The large intestine also includes the colon and the rectum where some absorption of water, vitamins, and minerals occur. Materials not absorbed in the colon are excreted from the body as waste in the feces. The colon is attached to the anus which is the external opening for the body and the end of the digestive track.