What happens if there is no mucus in the esophagus ?

Explanation

1) The walls of the food pipe secrete a slippery substance called mucus.
2) Mucus lubricates and protects the esophageal walls from damage .
3) This helps the food bolus to slide down easily in the tube .
4) If there is no mucus , lubrication will not done for the food bolus to slide and walls get damage .