The function of the digestive system is consumption and digestion, absorption, and elimination. Mechanical digestion happens when chewing starts and the saliva breaks down the food which is created by the salivary glands. Mucus is also secreted from the salivary glands to help guide food down when swallow. The food is then pass through the pharynx into the esophagus. Gastroparesis is when the stomach is not able to process the food content at it usual rate of emptying.
The stomach is in between the esophagus and small intestine; it joins the esophagus at the esophagogastric junction which is close to the diaphragm. As the stomach holds fluid and food it enlarges. Within the stomach rugae are present, these rugae are also known as mucosal folds. On the medial side of stomach, the rugae guides fluids down to the distal part of the stomach. Rugae is present in the stomach to aid as a mechanical digestion