Digestion

The digestion of a cheeseburger starts in the mouth. The saliva contains enzymes, amylase and lipase, that begin to break down the food. Amylase starts to break down carbohydrates, and lipase begins to breakdown fats. The saliva moistens the food and begins to liquify it. The cheeseburger then would travel down the esophagus through peristalsis, which is a coordinated movement of food along the digestive tract. Once the cheeseburger enters the stomach, food is broken down by enzymes and segmentation, or food mixing. Cheif cells in the stomach secrete pepsiogen, which once it enters the stomach becomes pepsin. Pepsin breaks larger proteins into smaller pieces. Parietal cells secrete hydrochloric acid which denatures proteins. The food them travels into the small intestine where chemical digestion continues until completion. By the time the food enters the large intestine, its nutrients have fully been absorbed. The main function of the large intestine is compaction of waste and absorption of water.