Digestion, How to Understand and Cope
Digestion is the body’s process to utilize food. It begins in the mouth, where rinding teeth produce small pieces. The three salivary glands secrete ptyilin, an enzyme which converts starch to sugars. Hold a bite of cracker in your mouth. As it dissolves, you’ll taste sugar as the ptyilin works.
The masticated food slides down the esophagus to the stomach, entering through the pyloric sphincter which is supposed to prevent back-flow, but doesn’t always—GERD, vomiting, burps, result from pyloric malfunction,
Food enters the stomach. Here it encounters several digestive enzymes, secreted by the liver, gall bladder, pancreas, the stomach itself. Some enzymes are secreted directly in the stomach mixture,’chyme’ and others in the circulation, e.g. insulin and glucagon, vital for blood glucose regulation, and enzymes which directly break down fats and proteins.
Below the stomach are the duodenum, jejunum, ileum and about twenty feet of small intestine, leading to the large one. Most digestion occurs here, larger quantities of liver, pancreas, cholecystokinin and others completing the digestive process.
The masticated, chymed, exhausted food finally makes it to the large intestine, then anus and rectum. Never mind about them. (Unless there are hemorrhoids.)