This illustration of the upper parts of the digestive system shows that a long tube called the esophagus connects the throat to the stomach, which is located in the upper abdomen. The topmost part of the stomach is the fundus, which bulges upward. The curved body of the stomach is filled with gastric folds. The lower portion of the stomach is the pyloric antrum, which leads to the pylorus, or pyloric canal. The pylorus connects to the duodenum, which is the first section of the small intestine.