What are the main parts of the ENT system
ears, nose, throat, lymph nodes, hearing and smell.
What structures make up the external ear? middle? internal?
External: pinna, external auditory canal, TM, helix.
Middle: ET tube, tympanic cavity w/ ossicles
Inner: vestibule, semicircular canals, cochlea
Blood supply to..
- the ear
- the nose
- the mouth
- the larynx
- the jaw
- the neck
Ear: External Carotid Artery
Nose: branches of ophthalmic and maxillary artery (internal carotid artery)
Mouth: sublingual, lingual, deep, and dorsal lingual arteries… which branch from external carotid
Larynx: superior laryngeal…branch of external carotid
Jaw: external carotid
Neck: common carotids
What are the nerves that supply the..
- external ear
- middle ear
- inner ear
external: arnolds nerve branch of the vagus nerve
middle: no one cares.
inner: facial and vestibulocochlear nerve
Purpose of the Eustachian Tube
- air exchange (pressure)
- excretory (drain middle ear)
- defense (preventing infection)
Which portions of the basilar membrane (of the cochlea) transfer lower and higher frequencies?
Apical portion (most curled) transfers lower frequencies
basal end relays higher frequencies
What direction does each of the following semicircular canals respond to?
- superior
- posterior
- lateral
superior: head up and down. yes movement
posterior: touching ear to shoulder
lateral: shake head NO, side to side.
what is ala nasi?
-the rounded lower borders of the nose
what bones make up each wall of the nasal cavity?
- roof
- floor
- medial
- lateral
Roof: frontonasal, ehtmoidal, sphenoidal
Floor: palatine process of maxilla, palantine bone
Medial: nasal septum, ethmoid bone, vomer, palatine bone
Lateral: 3 nasal conchae
Which area of the nose is most prone to bleeds?
-kiesselbach
Function of the nose
- respiration
- air conditioning
- protection
- olfaction
- eustachian tube =permits the nose to equalize pressure
- drainage
Which neuronal cells renew?
olfaction and gustatory
what nerve runs through the parotid gland and what are its branches?
- facial nerve runs through the parotid and it has 5 branches:
1. temporal
2. zygomatic
3. buccal
4. mandibular
5. cervical
What are the three parts of the tooth?
- crown: portion covered by enamel
- root
- pulp cavity: houses dental pulp = nerves, arteries, veins, and lymph channels
What are the taste buds and which do not actually taste?
filiform* = dont have taste buds (most front part of tongue)
fungiform
vallate
foliate
(most back part of tongue)
what are the 5 taste sensations? Describe their signal transduction
sweet(tip, upper 1/3)), sour(back 1/3), bitter (back), salty(middle 1/3), umami
salty and sour use Na and H channels whereas bitter and sweet use GPCR …CN VII (anterior 2/3), IX (posterior 1/3), and X carry these signals to the brain.
What are the muscles of the tongue?
4 extrinsic and 4 intrinsic
Extrinsic:
- genioglossus = protrudes tongue
- hyoglossus = depresses the tongue
- styloglossus = elevates and retracts tongue
- palatoglossus = depresses soft palate and depresses back of tongue
Intrinsic:
- superior longitudinal
- inferior longitudinal
- ventricle
- transverse
Nerve innervation of tongue
VII = facial, anterior 2/3
IX = glossopharyngeal, posterior 1/3
X and XII = motor. Vagus and hypoglossal
pharynx extends from the base of the skull to?..
the 6th cervical vertebrae
What is the blood/nerve supply to the pharynx?
Blood: facial artery
Nerve: maxillary, glossopharyngeal and vagus
Function of pharynx
swallowing
breathing
speech
equalize pressure in middle ear
immunity
function of larynx
producing voice, swallowing, breathing, protect the lower airway
larynx is composed of what three types of cartilage?
(superior) epiglottis….thyroid….cricoid (inferior)
Glottis is open during sound production?
FALSE!! its closed during sound production.. and open during breathing
Vocal cords voice mechanism
- air pressure system (regulates air pressure to cause vocal fold vibration)
- vibratory system (voice box, converts vibration to sound waves)
- resonating system (changes buzzy sound into recognizable voice)
Nerve supply to the larynx?
superior laryngeal nerve and recurrent laryngeal branch of the vagus nerve.
What muscles elevate the mandible to bite?
-masseter, temporalis, and lateral/medial pterygoid muscle
What are the margins of the anterior triangle of the neck? what are the 4 sub triangles this possesses?
Anterior triangle margins: midline, SCM, body of mandible.
- submental
- submandibular
- carotid
- muscular
What are the margins of the posterior cervical triangle? what are the 2 sub triangles?
clavical, SCM, trapezius
- occipital
- subclavian/supraclavicular