Final answer:
The muscles responsible for bolus propulsion are the pharyngeal constrictor muscles in the throat and the circular and longitudinal muscle layers of the muscularis in the esophagus.
Step-by-step explanation:
The muscles responsible for bolus propulsion are the pharyngeal constrictor muscles in the throat and the circular and longitudinal muscle layers of the muscularis in the esophagus. The contractions of the pharyngeal constrictor muscles push the bolus through the oropharynx and laryngopharynx, while peristalsis, which is the sequential contraction and relaxation of the circular and longitudinal muscles in the esophagus, propel the bolus toward the stomach.