gastrointestinal system (digestive system) - ANSWER -system of organs that breaks down foods into nutrients that the body can use
-ALSO known as
... [Show More] digestive system or the GI system
-accomplished by the processes of digestion and absorption
-controlled by the autonomic nervous system and regulated by series of hormonal feedback loops
-smooth muscle is effected by emotions
-sympathetic nervous system slows digestion and can cause the bowels to empty in preparation of dealing w/ a threat
-the parasympathetic nervous system increases blood flow to the stomach and intestine
-components: oral cavity, mouth, pharynx, esophagus, stomach, liver, gall bladder, duodenum, pancreas, jejunum, colon, ileum, cecum, vermiform appendix, rectum, and anus
digestion - ANSWER chemical and mechanical breakdown of foods into smaller compounds that can be utilized by the body
absorption - ANSWER -movement of a substance such as nutrients from the intestine to the bloodstream
-after foods have been digested, their nutrients are absorbed
alimentary canal - ANSWER -pathway through the body that food travels while being digested and absorbed, as well as the accessory organs that release secretions necessary for digestion to occur
-food enters the canal through the mouth
salivary glands - ANSWER release digestive enzymes that mix w/ the food to begin chemical digestion and lubricate the mouth
bolus - ANSWER -chewed food
-to be swallowed, first must be sensed by the pharynx
-bolus passes through the esophagus and then into the stomach
pharynx - ANSWER dividing point b/t the trachea and esophagus, where the throat senses the presence of food and triggers swallowing
esophagus - ANSWER portion of the alimentary canal b/t the pharynx and the stomach
peristalsis - ANSWER wavelike contraction of smooth muscle that moves digested material along the digestive tract
swallowing - ANSWER triggered when the chewed food (bolus) is sensed by the pharynx
stomach - ANSWER -both mechanical and chemical digestion continue in the stomach
-hollow organ separated from the esophagus by the esophageal sphincter and from the small intestine by the pyloric sphincter
-the pH of the stomach is maintained b/t 1 and 2 by the release of gastric juice, which contains hydrochloric acid (HCl) as well as enzymes that begin the chemical digestion of protein [Show Less]