What is peristalsis? Explain both mechanical as well as the chemical part of digestion of food in the mouth of man.

Peristalsis refers to the process by which the food is transported from the buccal cavity to the stomach with the help of the expansion and contraction of the muscles present in the oesophagus. After the peristaltic movement in the oesophagus, food particles move down the oesophagus and reach the stomach.

For the second part of the question, please follow the given link:
https://www.meritnation.com/ask-answer/question/what-is-mechanical-and-chemical-digestion/biology/666201