The tongue shapes chewed food into a spherical shape called a bolus. The bolus is formed when the tongue shapes food with the help of skeletal muscles. The swallowing process occurs when the tongue makes rhythmic movements, pushing the bolus towards the back of the mouth, for swallowing. Esophagus The esophagus, made up of numerous annular structures of strong muscles, performs a milking and squeezing action. This wave-like contraction of the smooth muscles around the tube is called peristalsis, and it is how most movements in the digestive system are performed. This action pushes the bolus down and into your stomach when you swallow. Liver The liver produces bile and secretes it into the small intestine. Bile, an emulsifier, causes large fat globules to break down into smaller particles. The hepatic ducts in the liver drain bile from the liver and secrete it into the small intestine, called the common bile duct. They have a variety of metabolic