Head & Neck 1 - Pharynx Flashcards
what are the three divisions of the pharynx?
nasopharynx, oropharynx, laryngopharynx
what type of muscles are the pharyngeal constrictor muscles - circular or longitudinal?
circular muscles
what are the pharyngeal constrictor muscles?
three circular muscles - superior, middle & inferior
what is the function of the pharyngeal constrictor muscles?
constrict sequentially to push food down the pharynx (peristalsis) - under conscious control but their sequential action isn’t
what nerve innervates the superior, middle & inferior pharyngeal constrictor muscles?
vagus nerve (via the pharyngeal plexus)
what are the three pharyngeal longitudinal muscles? what is their general action?
stylopharyngeus, palatopharyngeus, salpingopharyngeus
general action - shorten, widen, elevate pharynx during swallowing
what is the ONLY pharyngeal muscle not innervated by CN X? what is its innervation?
stylopharyngeus – innervated by glossopharyngeal nerve (CN9)
what is the main sensory nerve of the pharynx?
A) glossopharyngeal nerve (CN9)
B) vagus nerve (CN10)
C) hypoglossal nerve (CN12)
D) trigeminal nerve - maxillary branch (CNV2)
A) glossopharyngeal nerve (CN9)
what is the purpose of the gag reflex?
prevents foreign objects entering the airways by closing off the oropharynx
what muscles contract during the gag reflex? (4)
pharyngeal constrictors
pharyngeal longitudinal muscles
tongue
soft palate muscles
what cranial nerve provides the sensory (afferent) limb of the gag reflex?
glossopharyngeal nerve (CN9)
sensory stimulation of what structures triggers the gag reflex?
posterior 1/3 of tongue
tonsils
walls of oropharynx
what part of the tongue, upon sensory stimulation, triggers the gag reflex? - anterior 2/3 or posterior 1/3
posterior 1/3 - sensory stimulation via glossopharyngeal nerve
