Food enters the digestive system through the mouth. This process is called ingestion. Once in the mouth, the food is chewed to form a ball of food called a bolus. This passes down the oesophagus and into the stomach.
Food is moved through the digestive system by a process called peristalsis. Two sets of muscles in the gut wall are involved:
The muscles work together to produce wave-like contractions. These have a ‘squeezing action’ that pushes the bolus through the gut.