The stomach is an organ of digestion. It has a saclike shape and is located between the esophagus and the intestines. The human stomach is a muscular, elastic, pear-shaped bag, lying crosswise in the abdominal cavity beneath the diaphragm. It changes size and shape according to it’s position within the body and the amount of food ingested. The stomach is about 12 inches long and is 6 inches wide. The adult stomach can hold approximately 1 qt of food and water. Food enters the stomach via the esophagus. The connection between the stomach and the esophagus is called the cardiac sphincter. The cardiac sphincter prevents food from passing back through the esophagus. Once food enters the stomach, gastric juices are used to break down the food. The three primary functions of the stomach are to kill ingested bacteria, break down the food into smaller pieces for easier digestion, and to temporarily store food until it’s able to be fully digested.