The Pharynx Flashcards
the roof of the nasopharynx is formed by?
body of sphenoid and basal part of occipital bone
in relation to the larynx, the laryngopharynx lies?
posterosuperior
During swallowing, the bolus of food/drink is directed into the oropharynx then the oesophagus. What prevents this bolus from entering into the nasopharynx? and into the larynx?
uvula
epiglottis
the pharynx has three layers:
-
outer muscular layer which itself is made up of an:
- outer circular layer: formed by 3 constrictor (superior, middle and inferior) muscles. These muscles are arranged like flower pots placed inside one another, but are open in front at the entries of the nasal, buccal and laryngeal cavities.
- inner longitudinal layer: composed of the stylopharyngeus, salpingopharyngeus and palatopharyngeus muscles. - middle fibrous layer: merges with the deep fascia of the muscles and fills in gaps between muscles.
- inner mucous membrane
the pharynx recieves innervation from the…
pharyngeal plexus:
- formed by branches of the glossopharyngeal and vagus nerve.
which nerve provides sensory innervation to the pharynx?
glossopharyngeal
which nerve provides most of the motor innervation of the pharynx?
vagus
what is the role played by the constrictor muscles of the pharynx during swallowing?
propulsion of food bolus to the oesophagus
what is the role played by the longitudinal layer of muscles of the pharynx during swallowing?
shorten and widen the pharynx and elevate the larynx
what is the role played by the tongue and palate muscles during swallowing?
pressure to drive food into the oesoophagus, soft palate muscle closes way to nasal cavity.
describe the pharyngeal lymphoid ring (Waldeyer’s ring)
the pharyngeal lymphoid ring is a collection of lymphoid tissue that protects the entrance to the oropharynx
name the lymphoid collections present in Waldeyer’s ring
- 2 tubal tonsils
- 2 palatine tonsils
- pharyngeal
- lingual
