Checkpoint: Human Digestion

CheckPoint: Human Digestion

The sight and smell of food begins the digestion process with the salivary glands. Once food enters the mouth it is moistened by the saliva and grounded down by the teeth. The food transforms into a bolus. The bolus leaves the mouth and moves into the pharynx, where it is swallowed. The bolus moves from the pharynx to the esophagus, which moves the food to the stomach (University of Phoenix and Axia College, n.d.).

The stomach is an organ in the digestive tract that mixes food and secretes gastric juices. Once the bolus reaches the stomach, it mixes with the acid secretions to transform into chime, a semi liquid food mass. Food is partially digested in the stomach, and chime empties from the stomach in two to six hours, depending on the size and type of meal ingested (University of Phoenix and Axia College, n.d.).

After chime leaves the stomach it enters into the small intestine, which is divided into three parts known as the duodenum, the jejunum, and the ileum. Here the majority of digestion and absorption of nutrients from food takes place. Once food is in the small intestine, bile from the liver and gallbladder help with the digestion and absorption of fat, while enzymes and bicarbonate from the pancreas aid in the digestive process (University of Phoenix and Axia College, n.d.).

Materials not absorbed in the small intestine enter the large intestine through the sphincter. The sphincter keeps material from the large intestine from re-entering the small intestine. The large intestine includes the colon and the rectum. The colon is where the absorption of water and some vitamins occurs (University of Phoenix and Axia College, n.d.).

Materials not absorbed in the colon are excreted from the body as waste in the feces. The end of the colon is attached to the anus, which is where the feces is eliminated from the body.

University of Phoenix and Axia College. ( n.d.). SCI 225 Human Digestion Activity [Computer Software]. Retrieved from University of Phoenix and Axia College, Simulation, SCI 241 - Nutrition website.