Question

prestaltic movement of bolus

Answer 1

Contraction and relaxation of circular and longitudinal muscles bring in a wave - like motion that propels the food bolus into the stomach from oesophagus by the action called as peristalsis.
Experiment:
Aim: Making a mode of oesophagus to observe how bolus moves forward.
Material required : Potatoes, cycle tube lubricate oil
Procedure:

Take a piece of waste cycle tubes and insert . one or two potatoes into it.Lubricate the inner side of the tube with oil.In the same way smear oil over potatoes.Insert oil coated potatoes in the tube.Now try to push the potatoes by squeezing the tube from behind the potato.
Observation: Oil acted as lubricant to push the potato easily in the forward direction.
Conclusion : The muscles in the wall of the oesophagus have bring in a wave like movement due to contraction and relaxation, that propels the food bolus into the stomach.
This action is called as peristalisis

Answer 2

human gastrointestinal tract