Answer :
The esophagus undergoes peristalsis and the muscular movements force the bolus to the stomach, even against the force of gravity.
Which is not an involuntary part of the swallowing reflex?
The tongue rolls chewed food into a bolus and pushes it to the oropharynx. larynx.
Thus, The esophagus undergoes peristalsis and the muscular movements force the bolus to the stomach.
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