ENT Anatomy and Physiology

Question 1

What are the main parts of the ENT system

Answer 1

ears, nose, throat, lymph nodes, hearing and smell.

Question 2

What structures make up the external ear? middle? internal?

Answer 2

External: pinna, external auditory canal, TM, helix.

Middle: ET tube, tympanic cavity w/ ossicles

Inner: vestibule, semicircular canals, cochlea

Question 3

Blood supply to..

• the ear
• the nose
• the mouth
• the larynx
• the jaw
• the neck

Answer 3

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

Question 4

What are the nerves that supply the..

• external ear
• middle ear
• inner ear

Answer 4

external: arnolds nerve branch of the vagus nerve
middle: no one cares.
inner: facial and vestibulocochlear nerve

Question 5

Purpose of the Eustachian Tube

Answer 5

• air exchange (pressure)
• excretory (drain middle ear)
• defense (preventing infection)

Question 6

Which portions of the basilar membrane (of the cochlea) transfer lower and higher frequencies?

Answer 6

Apical portion (most curled) transfers lower frequencies

basal end relays higher frequencies

Question 7

What direction does each of the following semicircular canals respond to?

• superior
• posterior
• lateral

Answer 7

superior: head up and down. yes movement
posterior: touching ear to shoulder
lateral: shake head NO, side to side.

Question 8

what is ala nasi?

Answer 8

-the rounded lower borders of the nose

Question 9

what bones make up each wall of the nasal cavity?

• roof
• floor
• medial
• lateral

Answer 9

Roof: frontonasal, ehtmoidal, sphenoidal

Floor: palatine process of maxilla, palantine bone

Medial: nasal septum, ethmoid bone, vomer, palatine bone

Lateral: 3 nasal conchae

Question 10

Which area of the nose is most prone to bleeds?

Answer 10

-kiesselbach

Question 11

Function of the nose

Answer 11

• respiration
• air conditioning
• protection
• olfaction
• eustachian tube =permits the nose to equalize pressure
• drainage

Question 12

Which neuronal cells renew?

Answer 12

olfaction and gustatory

Question 13

what nerve runs through the parotid gland and what are its branches?

Answer 13

• facial nerve runs through the parotid and it has 5 branches:
  1. temporal
  2. zygomatic
  3. buccal
  4. mandibular
  5. cervical

Question 14

What are the three parts of the tooth?

Answer 14

• crown: portion covered by enamel
• root
• pulp cavity: houses dental pulp = nerves, arteries, veins, and lymph channels

Question 15

What are the taste buds and which do not actually taste?

Answer 15

filiform* = dont have taste buds (most front part of tongue)

fungiform

vallate

foliate
(most back part of tongue)

Question 16

what are the 5 taste sensations? Describe their signal transduction

Answer 16

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.

Question 17

What are the muscles of the tongue?

Answer 17

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

Question 18

Nerve innervation of tongue

Answer 18

VII = facial, anterior 2/3

IX = glossopharyngeal, posterior 1/3

X and XII = motor. Vagus and hypoglossal

Question 19

pharynx extends from the base of the skull to?..

Answer 19

the 6th cervical vertebrae

Question 20

What is the blood/nerve supply to the pharynx?

Answer 20

Blood: facial artery

Nerve: maxillary, glossopharyngeal and vagus

Question 21

Function of pharynx

Answer 21

swallowing

breathing

speech

equalize pressure in middle ear

immunity

Question 22

function of larynx

Answer 22

producing voice, swallowing, breathing, protect the lower airway

Question 23

larynx is composed of what three types of cartilage?

Answer 23

(superior) epiglottis….thyroid….cricoid (inferior)

Question 24

Glottis is open during sound production?

Answer 24

FALSE!! its closed during sound production.. and open during breathing

Question 25

Vocal cords voice mechanism

Answer 25

• 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)

Question 26

Nerve supply to the larynx?

Answer 26

superior laryngeal nerve and recurrent laryngeal branch of the vagus nerve.

Question 27

What muscles elevate the mandible to bite?

Answer 27

-masseter, temporalis, and lateral/medial pterygoid muscle

Question 28

What are the margins of the anterior triangle of the neck? what are the 4 sub triangles this possesses?

Answer 28

Anterior triangle margins: midline, SCM, body of mandible.

1. submental
2. submandibular
3. carotid
4. muscular

Question 29

What are the margins of the posterior cervical triangle? what are the 2 sub triangles?

Answer 29

clavical, SCM, trapezius

1. occipital
2. subclavian/supraclavicular