Final answer:
The pharyngeal constrictors are responsible for swallowing, contracting to move the food bolus from the pharynx to the esophagus, and starting the process of peristalsis.
Step-by-step explanation:
The function of the pharyngeal constrictors is to assist in swallowing. These muscles contract rhythmically to move the food bolus from the pharynx to the esophagus. This action is part of the swallowing process known as deglutition, which is highly coordinated with other actions such as the elevation of the larynx and the closing of the epiglottis to prevent food from entering the respiratory tract. The contraction of these muscles is followed by the relaxation of the upper esophageal sphincter, which allows the bolus to enter the esophagus and continue toward the stomach.
Peristalsis begins in the pharynx and continues in the esophagus as a series of wave-like muscle contractions, pushing the bolus towards the stomach. The pharyngeal constrictors play an essential role in this initial stage of the digestive process.