Physicians and surgeons have demanding education and training requirements. Almost all physicians complete at least 4 years of undergraduate school, 4 years of medical school, and, depending on their specialty, 3 to 8 years in internship and residency programs.lmost all physicians complete at least 4 years of undergraduate school, 4 years of medical school, and, depending on their specialty, 3 to 8 years in internship and residency programs.
The throat and esophagus. As seen in the picture, the mouth is connected to the stomach through the throat and the esophagus.
The stomach is a C-shaped pouch that receives the food bolus from the esophagus. It aids both in mechanical and chemical digestion. Acting like a churn, the stomach mixes the food with gastric acid and breaks down the food into a milky substance known as chyme. The acid reduces the pH of the stomach, in the process allowing activation of an enzyme called pepsin. This starts the chemical digestive process. 1  1. 2  2. 3  3. 4  Next â.