Pharynx Flashcards
what is the pharynx?
a muscular tube connecting the oral and nasal cavities to the larynx and oesophagus
where does the pharynx start and end ?
starts - base of the skull
ends - C6 circuit cartilage
what are the 3 parts of the pharynx?
nasopharynx
oropharynx
laryngopharynx
what does the pharynx have a ring of and what is it made of
ring of lymphoid tissue
made from:
palatine tonsils
lingual tonsils
tubal tonsils
pharyngeal tonsils (adenoids)
what are the external muscles of the pharynx?
circular (constrictor) muscles
overlap each other
voluntary muscles
what nerve supplies the external pharynx muscles?
CN X
what do the external pharynx muscles exert onto?
midline raphe
in what order do the external pharynx muscles contract?
sequentially from superior to inferior
to constrict the lumen to push food bolus into the oesophagus
what are the internal muscles of the pharynx?
longitudinal muscles
what do the internal pharynx muscles do during swallowing and why?
contract
to shorten and widen the pharynx and elevate the larynx
this is to close the laryngeal inlet
what nerves supply the internal pharynx muscles?
CN X supplies 2
CN IX supplies 1
what is the gag reflex?
a protective reflex
stops food going into the trachea
what is the posterior oropharynx extremely sensitive to?
touch
what carries the sensory part of the gag reflex?
nerve fibres within CN IX
what carries the motor part of the gag reflex?
nerve fibres whiting CN IX and CN X
