Which part of the human body contains the cardiac sphincter?

The cardiac sphincter, also known as the lower esophageal sphincter, is located at the junction of the esophagus and the stomach. Its primary function is to prevent the backflow of stomach contents into the esophagus, which can cause discomfort and conditions such as gastroesophageal reflux disease (GERD). This sphincter is a crucial component of the digestive system, which is responsible for the breakdown of food and the absorption of nutrients. The presence of the cardiac sphincter directly ties it to the digestive processes, making the digestive system the correct and relevant context for this anatomical feature.