-It is the continuation of the esophagus above and the duodenum of the small intestine below
-The stomach stores food and aids in digestion
-The wall of the stomach has deep folds which disappears as the stomach fills
-stomach has a capacity of approx. 1liter
-the wall churns mixing the food with the gastric juices (gastric always refers to the stomach)
-the rugae make it easier to churn the foodàcreates a rougher surface for the food to be mixed
-The columnar epithelial lining of the stomach mucosa has millions of gastric pitsàwhich lead into gastric glands the gastric glands produce gastric juices
-gastric juices produce an enzyme called pepsin, which digests protein and HCl and mucus
-the enzyme pepsin breaks the protein into peptides protein+wateràpeptides
-the HCl causes the stomach to have a low pH of about2 this is beneficial because it kills most bacteria present in food
-HCl does not digest food, it breaks down the connective tissue of meat and activates pepsin
-The wall of the stomach is protected by a thick layer of mucus secreted by goblet cells in its lining
-if HCl penetrates the mucus the HCl can break down the wall and an ulcer will occur
-Alcohol is absorbed in the stomach but food substances are not
-normally the stomach empties in about 2-6 hours
-when food leaves finally it is a thick soupy liquid called chyme
-chyme enters the small intestine through the way of the Pyloric sphincter the link between the esophagus and the stomach.
-The function of the Cardiac sphincter is to prevent the gastric acids (Hydrochloric acid) from entering the esophagus also known as heart burn. This sphincters muscles contract to open and close as food travels down the esophagus.
-Pyloric Sphincter: the function of this sphincter is to regulate the flow of chyme into the duodenum and it prevents the regurgitation of chyme from the small intestine to the stomach, chyme enters the small intestine through squirts by the sphincter because it repeatedly opens and close
No comments:
Post a Comment