Nutrition1 Essay Example | Topics and Well Written Essays - 750 words

Nutrition1 - Essay Example The esophagus is a tube made of strong muscles that connect the mouth and the stomach. The bolus goes down to the stomach through it using peristaltic waves. The esophageal sphincter at its lower end makes the food stay in the stomach (Brown, 2011). In the stomach, the chewed food is stored for a while to allow the body to digest it properly. The food is mixed with the gastric acid that contains hydrochloric acid and sodium chloride. The hydrochloric acid destroys any bacteria that may have been ingested together with the food. Gastrin is the hormone that arouses the G cells to produce the gastric acid. The acid then stimulates the conversion of pepsinogen to pepsin that digests proteins. So as to avoid the corrosion of the stomach, there is a lining of mucus around it. As the food continues being mixed to form a thick liquid called chyme, the enzyme gastric lipase starts the chemical breakdown of fat globules in the food though not completely. The glycoprotein known as intrinsic factor is produced by the parietal cells to help in the absorption of vitamin B12. Food components that are in their simplest form like glucose are absorbed in the stomach. The peristaltic movements of the stomach then push the food down to the small i ntestines. The food is blocked from re-entering the stomach by the pyloric sphincter (Brown, 2011). The small intestines are the lower part of the alimentary canal where most of nutrient absorption takes place. The duodenum makes the initial phase of the small intestines where the acidic chime is made alkaline through the action of bile from the gall bladder; bicarbonates form the Brunner’s glands and the bicarbonates from the pancreas. Bile that is produced by the liver is stored in the gall bladder. The enzyme pancreatic lipase further breaks down the fat molecules called chylomicrons. The pancreatic juice also digests carbohydrates to glucose and proteins to amino acids. The lining of the stomach has many