Final answer:
Swallowing, or deglutition, indeed comprises a voluntary phase where you can control the initiation of swallowing, followed by involuntary reflex actions—the pharyngeal and esophageal phases—that move the food towards the stomach.
Step-by-step explanation:
True. Swallowing consists of both a voluntary phase and reflex action, which are integral to what is known as deglutition. The process of deglutition, or swallowing, includes three phases: the voluntary phase, the pharyngeal phase, and the esophageal phase. The voluntary phase involves conscious control, where you initiate swallowing after chewing is completed. Your tongue pushes the food to the back of your oral cavity.
The pharyngeal phase, an involuntary reflex action, starts when the bolus of food triggers receptors. It prompts the deglutition center in the medulla oblongata to orchestrate movements that prevent food from entering the respiratory pathways. During this phase, swallowing temporarily disrupts breathing.
Finally, the esophageal phase is another reflexive action where peristalsis takes over, moving the food into the stomach. Both the pharyngeal and esophageal phases are controlled by the autonomic nervous system and involve complex neuromuscular actions.