When food moves through the esophagus, the muscular contractions are wave-like. nutrients are absorbed in the esophagus. skeletal muscle carries out all of the muscular contractions of the wall. the muscular contractions are entirely involuntary. gravity is necessary to move food toward the stomach?

The answers are;

The muscular contractions are wave-like

The muscular contractions are entirely involuntary

This action is called peristalsis. It is powered by the expansion and contraction of the smooth muscles present in the esophagus. It is controlled by the sympathetic activity of the autonomic nervous system hence the movements are involuntary.