Throat anatomy and Physiology Flashcards
what are the 3 subdivisions of the pharynx?
nasopharynx
oropharynx
hypopharynx
what are the 2 parts of the oral cavity?
oral vestibule (between lips and teeth) oral cavity proper
what are the boundaries of the oral cavity?
lips to palatoglossal arch
palate to floor of mouth/tongue
buccal mucosa
what muscle does the parotid duct pierce?
buccinator
what muscle does the submandibular duct lie superior to?
digastric muscle
what muscle separates the deep and superficial lobes of the submandibular duct?
mylohyloid
what does the lingual nerve supply?
general somatic afferent innervation from the anterior 2/3ds of the tongue.
what is the lingual nerve a branch of?
mandibular branch of trigeminal nerve
what special nerve fibres does the lingual nerve carry?
chorda tympani nerve of the facial nerve
what is the function of the chorda tympani?
provides special sensation (taste) to the anterior 2/3 of tongue
what are the functions of the oral cavity?
taste mastication speech digestion swallowing
what are the anterior 2/3ds of the tongue formed from embryologically?
1st branchial arch
what is the posterior 1/3 of the tongue formed from embryologically?
3rd branchial arch
what supplies the posterior part of the tongue?
glossopharyngeal nerve
what 2 types of muscles are contained in the tongue?
intrinsic
extrinsic
what is the function of intrinsic muscles of the tongue?
alters shape
what is the function of extrinsic muscles of the tongue?
alters position
what supples the muscles of the tongue?
hypoglossal nerve supplies everything except the palatoglossus
what nerve supplies the palatoglossus?
pharyngeal plexus
what muscles participate in mastication (chewing)
lateral pterygoid
medial pterygoid
temporalis
masseter
what nerve controls mastication
CN V3 (mandibular nerve)
what joint do the muscles of chewing act upon?
the temporomandibular joint
what are the boundaries of the oropharynx?
lower border of soft palate to upper margin of epiglottis
palatoglossal arch to posterior pharyngeal wall
lateral: faucal pillars and palatine tonsils
what type of epithelium lines the oropharynx?
stratified, non keratinised squamous
what nerves supply the oro pharynx?
pharyngeal plexus - CN IX and X
what are the extrinsic muscles of the tongue?
genioglossus
styloglossus
hyoglossus
palatoglossus
what arteries supply the hypopharynx?
superior thyroid artery
lingual artery
ascending pharyngeal artery
what nerves supply the hypopharynx?
pharyngeal plexus
what are the boundaries of the hypopharynx?
superior margin of the epiglottis to lower border of the cricoid cartilage
continuous with the oesophagus
anterior wall: back of larynx
what 3 subsites is the hypopharynx divided into?
pyriform sinus
post cricoid area
posterior pharyngeal wall
what are the 3 phases of swallowing?
oral phase (voluntary)
pharyngeal phase
oesophageal phase
what afferent nerves are involved in the oral phase of swallowing?
CN: V, IX, X
efferent: CN VII, X XII
where in the brain is the “swallowing centre” located
medulla
describe the steps in the pharyngeal phase of swallowing?
- soft palate pulled upwards
- epiglottis covers the laryns, vocal cords approximate, larynx moves upwards
- UOS relaxes
- respiration is reflex inhibited
describe the steps in the oesophageal phase of swallowing
once bolus passed UOS, sphincter constricts
bolus propelled downwards via peristaltic motion, reflex via myenteric plexus
what are the 3 parts of the larynx?
supraglottis
glottis
subglottic
what are the 7 segments of cartilage in the larynx?
cricoid cartilage
thyroid cartilage
epiglottis
paired arytenoid cartilages (corniculate and cuneiform)
what are the extrinsic muscles of the larynx?
infrahyoid
suprahyoid
thyrohyoid
what is the function of the extrinsic muscles of the larynx
move the entire laryngeal complex
what are the intrinsic muscles of the larynx?
posterior crico-arytenoid oblique arytenoids transverse arytenoid lateral crico-arytenoids thyro-arytenoids
what is the function of the intrinsic muscles of the larynx?
regulate movement of the vocal chords
what is responsible for motor innervation of the larynx?
CN X
what nerve supplies all intrinsic larynx muscles? (motor)
recurrent laryngeal nerve except for cricothyroid muscle (external laryngeal nerve)
what provides sensory innervation to the larynx?
supraglottic: internal laryngeal nerve
glottic and subglottic:
recurrent laryngeal nerve
why is there a higher risk of injuring the left recurrent laryngeal nerve during surgery?
it has a longer course since it loops around the aortic arch os opposed to the right subclavian artery and therefore has a higher risk of injury during operative chest procedures
what are the 5 steps of speech?
respiration phonation resonation articulation prosody
