Ear in Human Anatomy MCQ Questions and Answers

1. The external auditory canal (meatus) is lined laterally by:
A) Respiratory epithelium
B) Keratinized stratified squamous epithelium (skin) with hair and ceruminous glands
C) Simple cuboidal epithelium
D) Pseudostratified ciliated columnar epithelium
Answer: B) Keratinized stratified squamous epithelium (skin) with hair and ceruminous glands

2. The tympanic membrane’s pars tensa receives its radial and circular fibers from the:
A) Tensor tympani muscle
B) Lamina propria of tympanic membrane (middle fibrous layer)
C) Chorda tympani nerve
D) Malleus neck only
Answer: B) Lamina propria of tympanic membrane (middle fibrous layer)

3. The handle (manubrium) of the malleus is attached to the tympanic membrane at the:
A) Umbo
B) Umbo (central depressed point where manubrium attaches)
C) Annulus only
D) Long process of incus
Answer: B) Umbo (central depressed point where manubrium attaches)

4. The ossicle that articulates with the oval window is the:
A) Malleus
B) Incus
C) Stapes (footplate at oval window)
D) Hyoid bone
Answer: C) Stapes (footplate at oval window)

5. The tensor tympani muscle is innervated by:
A) Facial nerve (CN VII)
B) Mandibular division of trigeminal nerve (V3)
C) Glossopharyngeal nerve (IX)
D) Vagus nerve (X)
Answer: B) Mandibular division of trigeminal nerve (V3)

6. The stapedius muscle receives its motor innervation from the:
A) Mandibular nerve (V3)
B) Facial nerve (CN VII) — nerve to stapedius
C) Glossopharyngeal nerve (IX)
D) Hypoglossal nerve (XII)
Answer: B) Facial nerve (CN VII) — nerve to stapedius

7. Contraction of the stapedius muscle primarily results in:
A) Increased amplitude of stapes motion
B) Dampening of low-frequency sound transmission (protection against loud sounds)
C) Opening of Eustachian tube
D) Protrusion of malleus laterally
Answer: B) Dampening of low-frequency sound transmission (protection against loud sounds)

8. The Eustachian (auditory) tube in adults runs:
A) Horizontally from nasopharynx to middle ear
B) Obliquely downward, forward and medially from middle ear to nasopharynx
C) Vertically from external meatus to nasopharynx
D) Posteriorly from nasopharynx to mastoid antrum
Answer: B) Obliquely downward, forward and medially from middle ear to nasopharynx

9. Otosclerosis typically causes conductive hearing loss by fixation of which ossicle?
A) Malleus head
B) Stapes footplate at oval window
C) Incus long process
D) Stapedial tendon
Answer: B) Stapes footplate at oval window

10. The mastoid air cells drain into the middle ear via the:
A) Eustachian tube directly
B) Mastoid antrum (aditus ad antrum) connecting to epitympanum
C) Round window niche
D) Carotid canal
Answer: B) Mastoid antrum (aditus ad antrum) connecting to epitympanum

11. The facial nerve gives off the chorda tympani in which segment of its course?
A) Intracranial before internal acoustic meatus
B) Within the facial canal (tympanic segment) — branch passes through middle ear
C) Extracranial after stylomastoid foramen only
D) At geniculate ganglion into submandibular duct
Answer: B) Within the facial canal (tympanic segment) — branch passes through middle ear

12. The round window separates the scala tympani from the:
A) Scala vestibuli directly
B) Middle ear cavity (round window membrane faces middle ear)
C) Vestibule only
D) Eustachian tube lumen
Answer: B) Middle ear cavity (round window membrane faces middle ear)

13. The bony labyrinth contains three principal components except:
A) Cochlea
B) Vestibule
C) Tympanic membrane
D) Semicircular canals
Answer: C) Tympanic membrane

14. The membranous labyrinth is filled with:
A) Perilymph
B) Endolymph
C) Air
D) Blood
Answer: B) Endolymph

15. The ionic composition of endolymph is characterized by:
A) High Na+, low K+
B) High K+, low Na+ (unusual among extracellular fluids)
C) Equal K+ and Na+
D) High Ca2+ only
Answer: B) High K+, low Na+ (unusual among extracellular fluids)

16. The stria vascularis is the major site of production of:
A) Perilymph
B) Endolymph (maintains high K+ concentration)
C) Cerebrospinal fluid
D) Synovial fluid
Answer: B) Endolymph (maintains high K+ concentration)

17. The organ of Corti sits on which membrane?
A) Reissner’s membrane
B) Basilar membrane
C) Tectorial membrane only
D) Oval window membrane
Answer: B) Basilar membrane

18. Hair cell stereocilia of the organ of Corti contact which membrane to transduce mechanical vibrations?
A) Reissner’s membrane only
B) Tectorial membrane (outer hair cells embedded; inner hair cells near)
C) Round window membrane only
D) Basilar membrane directly without any overlying membrane
Answer: B) Tectorial membrane (outer hair cells embedded; inner hair cells near)

19. The function of outer hair cells in the cochlea is primarily to:
A) Transmit auditory nerve action potentials only
B) Amplify and sharpen basilar membrane motion (cochlear amplifier)
C) Produce endolymph
D) Close the round window actively
Answer: B) Amplify and sharpen basilar membrane motion (cochlear amplifier)

20. The primary afferent fibers of the cochlea course centrally in which nerve?
A) Facial nerve (VII)
B) Glossopharyngeal nerve (IX)
C) Cochlear division of vestibulocochlear nerve (CN VIII)
D) Trigeminal nerve (V)
Answer: C) Cochlear division of vestibulocochlear nerve (CN VIII)

21. High-frequency sounds are detected at which region of the cochlea?
A) Apex (apical turn)
B) Base (near oval window)
C) Helicotrema only
D) Round window niche only
Answer: B) Base (near oval window)

22. The first central relay nucleus for auditory nerve fibers within the brainstem is the:
A) Inferior colliculus
B) Superior olivary complex
C) Cochlear nucleus (dorsal and ventral)
D) Medial geniculate body
Answer: C) Cochlear nucleus (dorsal and ventral)

23. Sound localization using interaural time differences is primarily processed at the:
A) Lateral geniculate body
B) Medial superior olive (MSO)
C) Inferior colliculus only
D) Dorsal cochlear nucleus only
Answer: B) Medial superior olive (MSO)

24. The lateral superior olive (LSO) is mainly involved in encoding:
A) Interaural time differences for low frequencies
B) Interaural level (intensity) differences for high frequencies
C) Olfactory signals only
D) Vestibular reflexes exclusively
Answer: B) Interaural level (intensity) differences for high frequencies

25. The auditory pathway from inferior colliculus projects to the auditory cortex via the:
A) Superior colliculus only
B) Medial geniculate body of thalamus
C) Lateral geniculate body
D) Amygdala directly
Answer: B) Medial geniculate body of thalamus

26. Conduction deafness produces which Rinne/Weber test pattern?
A) Rinne positive; Weber midline
B) Rinne negative in affected ear; Weber lateralizes to affected ear
C) Rinne positive; Weber lateralizes to opposite ear
D) Rinne negative both sides; Weber midline
Answer: B) Rinne negative in affected ear; Weber lateralizes to affected ear

27. Sensorineural hearing loss produces which Rinne/Weber pattern?
A) Rinne negative; Weber to impaired ear
B) Rinne positive (air > bone) but decreased overall; Weber lateralizes to good ear (opposite ear)
C) Rinne negative both sides; Weber midline
D) Rinne positive; Weber midline always
Answer: B) Rinne positive (air > bone) but decreased overall; Weber lateralizes to good ear (opposite ear)

28. The vestibulo-ocular reflex (VOR) stabilizes vision during head rotation and uses which pair of structures?
A) Cochlea and auditory cortex
B) Semicircular canals (angular acceleration) and extraocular muscles via vestibular nuclei and CN III/IV/VI
C) Utricle exclusively and olfactory bulb
D) Tympanic membrane and stapes
Answer: B) Semicircular canals (angular acceleration) and extraocular muscles via vestibular nuclei and CN III/IV/VI

29. The superior semicircular canal senses rotation primarily in which plane?
A) Horizontal (yaw) plane
B) Sagittal (pitch) plane — head nodding / superior canal linked to roll/pitch depending on orientation)
C) Vertical only
D) No angular motion, only linear
Answer: B) Sagittal (pitch) plane — head nodding / superior canal linked to roll/pitch depending on orientation)

30. The utricle and saccule detect:
A) Angular acceleration only
B) Linear acceleration and static head position (gravity) via otolithic organs)
C) Sound frequency only
D) Temperature changes in inner ear
Answer: B) Linear acceleration and static head position (gravity) via otolithic organs)

31. The otolithic membrane contains which crystals responsible for inertia sensing?
A) Cholesterol crystals
B) Otoliths (otoconia — calcium carbonate crystals)
C) Keratin flakes only
D) Hemoglobin deposits
Answer: B) Otoliths (otoconia — calcium carbonate crystals)

32. Benign paroxysmal positional vertigo (BPPV) is usually caused by:
A) Perilymph fistula only
B) Displaced otoconia (canalithiasis) in a semicircular canal (often posterior canal)
C) Labyrinthitis due to virus only
D) Vestibular schwannoma exclusively
Answer: B) Displaced otoconia (canalithiasis) in a semicircular canal (often posterior canal)

33. The nerve supplying general sensation to the external auditory canal and outer tympanic membrane is primarily:
A) Glossopharyngeal nerve (IX) only
B) Auriculotemporal nerve (V3) and contributions from facial, vagus, and great auricular nerves)
C) Hypoglossal nerve (XII) only
D) Olfactory nerve (I)
Answer: B) Auriculotemporal nerve (V3) and contributions from facial, vagus, and great auricular nerves)

34. The facial nerve (CN VII) paralysis due to a lesion in the facial canal within the temporal bone often first affects which reflex?
A) Jaw jerk reflex only
B) Stapedius reflex (hyperacusis due to stapedius paralysis)
C) Gag reflex only
D) Pupillary light reflex only
Answer: B) Stapedius reflex (hyperacusis due to stapedius paralysis)

35. The bony prominence forming the lateral wall of the middle ear is the:
A) Tegmen tympani
B) Promontory (cochlear promontory is medial wall)
C) Lateral canalicular process (tympanic)
D) Anterior wall only
Answer: B) Promontory (cochlear promontory is medial wall)

36. The tegmen tympani separates the middle ear from the:
A) Nasopharynx directly
B) Middle cranial fossa (temporal lobe) — roof of tympanic cavity
C) External auditory canal only
D) Internal carotid canal exclusively
Answer: B) Middle cranial fossa (temporal lobe) — roof of tympanic cavity

37. The pyramidal eminence in the middle ear contains the origin of which muscle?
A) Tensor tympani
B) Stapedius
C) Levator veli palatini
D) Tensor veli palatini
Answer: B) Stapedius

38. A lesion of the vestibular nerve at the internal acoustic meatus typically produces:
A) Conduction hearing loss only
B) Acute vertigo, nystagmus and ipsilateral sensorineural hearing loss
C) Facial pain only
D) Loss of smell only
Answer: B) Acute vertigo, nystagmus and ipsilateral sensorineural hearing loss

39. The tympanic branch of the glossopharyngeal nerve (Jacobson’s) contributes to:
A) Motor to tensor tympani only
B) Tympanic plexus (sensory to middle ear mucosa) and presynaptic parasympathetic fibers to otic ganglion)
C) Taste from posterior tongue only
D) Motor to stapedius only
Answer: B) Tympanic plexus (sensory to middle ear mucosa) and presynaptic parasympathetic fibers to otic ganglion)

40. The main arterial supply to the inner ear is from the:
A) Superior thyroid artery
B) Internal auditory (labyrinthine) artery usually a branch of AICA or basilar artery
C) Maxillary artery directly
D) External carotid via superficial temporal branch
Answer: B) Internal auditory (labyrinthine) artery usually a branch of AICA or basilar artery

41. The internal auditory (labyrinthine) artery supplies all inner ear structures and courses within the:
A) Carotid canal
B) Internal acoustic meatus (accompanies CN VII and VIII)
C) Foramen rotundum
D) Superior orbital fissure
Answer: B) Internal acoustic meatus (accompanies CN VII and VIII)

42. The cochlear aqueduct connects perilymphatic space to the:
A) Endolymphatic sac only
B) Subarachnoid space (CSF) at the posterior cranial fossa — potential pressure communication)
C) Middle ear cavity directly
D) Eustachian tube lumen
Answer: B) Subarachnoid space (CSF) at the posterior cranial fossa — potential pressure communication)

43. Ménière’s disease is classically associated with which pathophysiology?
A) Otosclerosis at oval window only
B) Endolymphatic hydrops (excess endolymph in membranous labyrinth)
C) Cochlear nerve transection
D) Middle ear effusion only
Answer: B) Endolymphatic hydrops (excess endolymph in membranous labyrinth)

44. In the acoustic reflex, loud sounds cause bilateral contraction of which muscle(s)?
A) Tensor tympani only ipsilateral
B) Stapedius bilaterally (primarily ipsilateral via facial nerve, with contralateral component via brainstem)
C) Levator veli palatini only
D) Tensor veli palatini bilaterally
Answer: B) Stapedius bilaterally (primarily ipsilateral via facial nerve, with contralateral component via brainstem)

45. The round window functions physiologically to:
A) Transmit sound to cochlear duct directly
B) Allow displacement of perilymph in scala tympani when stapes moves at oval window (pressure relief)
C) Produce endolymph
D) Close the Eustachian tube
Answer: B) Allow displacement of perilymph in scala tympani when stapes moves at oval window (pressure relief)

46. The cochlear nerve’s cell bodies are located in:
A) Trigeminal ganglion
B) Spiral (cochlear) ganglion in the modiolus
C) Geniculate ganglion
D) Superior olivary nucleus
Answer: B) Spiral (cochlear) ganglion in the modiolus

47. The promontory of the middle ear corresponds to which inner ear structure underlying it?
A) Lateral semicircular canal
B) Basal turn of cochlea (cochlear promontory)
C) Round window niche only
D) Saccule exclusively
Answer: B) Basal turn of cochlea (cochlear promontory)

48. The tympanic membrane is supplied arterially primarily by which vessels?
A) Posterior auricular artery only
B) Deep auricular (from maxillary) and auricular branches from superficial temporal and posterior auricular arteries
C) Superior thyroid artery only
D) Vertebral artery only
Answer: B) Deep auricular (from maxillary) and auricular branches from superficial temporal and posterior auricular arteries

49. Cholesteatoma is best described as:
A) A primary malignant tumor of middle ear mucosa
B) A keratinizing squamous epithelial cyst (destructive) in middle ear/mastoid
C) Otosclerosis variant in tympanic membrane
D) Fungal colony in external canal only
Answer: B) A keratinizing squamous epithelial cyst (destructive) in middle ear/mastoid

50. The lateral semicircular canal is approximately oriented in which plane?
A) Sagittal plane
B) Horizontal plane (detects rotation around vertical axis — yaw)
C) Coronal plane exclusively
D) Oblique only with no functional plane
Answer: B) Horizontal plane (detects rotation around vertical axis — yaw)

51. The vestibular hair cells are embedded in the:
A) Tectorial membrane only
B) Otolithic membrane in maculae; cupula in ampullae of semicircular canals
C) Basilar membrane only
D) Round window membrane
Answer: B) Otolithic membrane in maculae; cupula in ampullae of semicircular canals

52. The tympanic plexus lies on which wall of the middle ear?
A) Lateral wall only
B) Promontory (medial wall) — formed by tympanic branch of IX and sympathetic fibers
C) Floor only
D) Roof (tegmen) only
Answer: B) Promontory (medial wall) — formed by tympanic branch of IX and sympathetic fibers

53. The pyramidal eminence and facial canal relationship determine vulnerability of the facial nerve to middle ear disease. The facial nerve in the tympanic segment runs:
A) Lateral to the tympanic membrane within external canal
B) In the facial canal on the medial wall above the oval window, giving off nerve to stapedius
C) In the mastoid segment only and not in middle ear
D) Through the ossicles directly
Answer: B) In the facial canal on the medial wall above the oval window, giving off nerve to stapedius

54. The otic capsule (bony labyrinth) develops embryologically from:
A) Neural crest only
B) Mesenchyme (otic placode derivatives) undergoing chondrification and ossification around membranous labyrinth)
C) Endoderm only
D) Surface ectoderm of first arch
Answer: B) Mesenchyme (otic placode derivatives) undergoing chondrification and ossification around membranous labyrinth)

55. The pharyngotympanic tube closes at rest due to:
A) Strong muscular tone of tensor tympani
B) Flaccid resting position of tubal mucosa and closure by mucosal folds; opens during swallowing by tensor veli palatini and levator veli palatini
C) Constant negative middle ear pressure always
D) Bony occlusion in adults only
Answer: B) Flaccid resting position of tubal mucosa and closure by mucosal folds; opens during swallowing by tensor veli palatini and levator veli palatini

56. The oval window is located on which wall of the middle ear?
A) Lateral wall only
B) Medial wall (entrance to vestibule) adjacent to promontory
C) Roof (tegmen tympani) only
D) Floor (jugular wall) only
Answer: B) Medial wall (entrance to vestibule) adjacent to promontory

57. The cochlear duct (scala media) is bounded superiorly by:
A) Basilar membrane only
B) Reissner’s (vestibular) membrane and roofed by endolymph-containing scala media
C) Round window only
D) Oval window only
Answer: B) Reissner’s (vestibular) membrane and roofed by endolymph-containing scala media

58. The phase-locking mechanism in auditory nerve fibers contributes to encoding of:
A) Loudness only
B) Temporal (frequency) information for low-frequency sounds
C) Balance orientation only
D) Visual-aural reflex only
Answer: B) Temporal (frequency) information for low-frequency sounds

59. The Heschl’s gyrus located in the cerebral cortex corresponds to:
A) Primary motor cortex for facial muscles
B) Primary auditory cortex (Brodmann’s areas 41, 42) in superior temporal gyrus
C) Visual cortex only
D) Olfactory cortex only
Answer: B) Primary auditory cortex (Brodmann’s areas 41, 42) in superior temporal gyrus

60. The tympanic cavity’s inferior wall (floor) separates it from the:
A) Middle cranial fossa
B) Jugular fossa (internal jugular vein) and carotid canal area inferiorly
C) External auditory canal only
D) Internal acoustic meatus only
Answer: B) Jugular fossa (internal jugular vein) and carotid canal area inferiorly

61. Tympanometry measures which property of the middle ear system?
A) Pure tone thresholds only
B) Compliance (mobility) of tympanic membrane and ossicular chain with pressure changes
C) Auditory brainstem responses only
D) Endolymphatic pressure directly
Answer: B) Compliance (mobility) of tympanic membrane and ossicular chain with pressure changes

62. A Type B tympanogram (flat trace) typically suggests:
A) Normal middle ear function
B) Middle ear effusion (fluid) or perforated tympanic membrane depending on ear canal volume
C) Hypermobile tympanic membrane only
D) Superior semicircular canal dehiscence
Answer: B) Middle ear effusion (fluid) or perforated tympanic membrane depending on ear canal volume

63. The jugular bulb lies inferior to which middle ear wall?
A) Lateral wall only
B) Inferior (floor) wall of tympanic cavity
C) Roof/tegmen only
D) Posterior wall only
Answer: B) Inferior (floor) wall of tympanic cavity

64. The lateral process of the malleus articulates with:
A) Incus long process
B) Tympanic membrane (near pars flaccida region attachments)
C) Stapes footplate directly
D) None — it is vestigial only
Answer: B) Tympanic membrane (near pars flaccida region attachments)

65. The facial nerve’s labyrinthine segment ends at which landmark?
A) Stylomastoid foramen
B) Geniculate ganglion (first genu) where the nerve makes a sharp bend
C) Middle ear cavity only
D) Round window niche
Answer: B) Geniculate ganglion (first genu) where the nerve makes a sharp bend

66. The external auditory canal cartilage is continuous with which cartilage anteriorly?
A) Thyroid cartilage only
B) Auricular cartilage of pinna (elastic cartilage)
C) Cricoid cartilage only
D) Alar cartilage of nose
Answer: B) Auricular cartilage of pinna (elastic cartilage)

67. The cochlear microphonic potential is generated mainly by:
A) Inner hair cells only
B) Outer hair cells responding to basilar membrane motion (receptor potentials mimicking stimulus waveform)
C) Spiral ganglion action potentials only
D) Efferent fibers of cochlear nucleus
Answer: B) Outer hair cells responding to basilar membrane motion (receptor potentials mimicking stimulus waveform)

68. The acoustic neuroma (vestibular schwannoma) most commonly arises from which cell layer?
A) Schwann cells of cochlear or vestibular nerve (usually vestibular branch)
B) Schwann cells (myelinating cells) of vestibular portion of CN VIII at the internal acoustic meatus)
C) Meningothelial cells only
D) Epithelial lining of middle ear only
Answer: B) Schwann cells (myelinating cells) of vestibular portion of CN VIII at the internal acoustic meatus)

69. A perilymphatic fistula most commonly occurs at which anatomical sites?
A) External auditory canal cartilage only
B) Round window or oval window (rupture causing perilymph leak)
C) Mastoid antrum only
D) Cochlear aqueduct only
Answer: B) Round window or oval window (rupture causing perilymph leak)

70. The chorda tympani carries which fibers?
A) Purely motor to tensor tympani
B) Taste fibers from anterior two-thirds of tongue and preganglionic parasympathetic fibers to submandibular ganglion
C) Motor to stapedius only
D) Somatic sensory to external ear only
Answer: B) Taste fibers from anterior two-thirds of tongue and preganglionic parasympathetic fibers to submandibular ganglion

71. The highest point of the tympanic membrane (pars flaccida) is attached to which structure?
A) Manubrium of malleus only
B) Attic/Prussak’s space region bounded by pars flaccida and lateral process of malleus
C) Round window membrane directly
D) Endolymphatic sac superiorly
Answer: B) Attic/Prussak’s space region bounded by pars flaccida and lateral process of malleus

72. The semicircular canals’ ampullae contain what sensory structure?
A) Macula with otoconia
B) Crista ampullaris (sensory ridge with hair cells and cupula)
C) Organ of Corti segments only
D) Spiral ligament
Answer: B) Crista ampullaris (sensory ridge with hair cells and cupula)

73. The vestibular nuclei located in the brainstem contribute fibers to which descending tract affecting posture?
A) Corticospinal tract only
B) Lateral and medial vestibulospinal tracts (postural reflexes, balance)
C) Spinothalamic tract only
D) Dorsal column exclusively
Answer: B) Lateral and medial vestibulospinal tracts (postural reflexes, balance)

74. The labyrinthine window niche containing the stapes footplate is directly adjacent to which cranial nerve structure?
A) Facial nerve geniculate ganglion only
B) Facial nerve canal and chorda tympani courses posteriorly; facial nerve tympanic segment is nearby
C) Trigeminal ganglion only
D) Glossopharyngeal nerve only
Answer: B) Facial nerve canal and chorda tympani courses posteriorly; facial nerve tympanic segment is nearby

75. The best surgical approach for exposure of the internal auditory canal & cerebellopontine angle for vestibular schwannoma is:
A) Middle ear tympanoplasty only
B) Translabyrinthine or retrosigmoid approaches (choice depends on hearing preservation goals)
C) Transnasal endoscopic only
D) External canal meatoplasty only
Answer: B) Translabyrinthine or retrosigmoid approaches (choice depends on hearing preservation goals)

76. The tympanic membrane’s blood supply on its outer surface is predominantly from:
A) Internal carotid via labyrinthine artery
B) External carotid branches — deep auricular (from maxillary), posterior auricular, and superficial temporal arteries
C) Middle meningeal artery only
D) Vertebral artery
Answer: B) External carotid branches — deep auricular (from maxillary), posterior auricular, and superficial temporal arteries

77. The ampullary cupula deflects in response to endolymph movement during:
A) Slow linear acceleration only
B) Angular acceleration (rotation) of the head
C) Changes in blood pressure only
D) Sound wave entry into cochlea
Answer: B) Angular acceleration (rotation) of the head

78. The typical first symptom of vestibular schwannoma (acoustic neuroma) is:
A) Facial paralysis immediately in all cases
B) Unilateral progressive sensorineural hearing loss and tinnitus
C) Sudden conductive hearing loss bilaterally
D) Profound vertigo only without hearing involvement
Answer: B) Unilateral progressive sensorineural hearing loss and tinnitus

79. The tympanic membrane is oriented obliquely so that its inferior part faces:
A) Anterosuperiorly only
B) Laterally and slightly anteriorly; inferior margin projects more medially (clinical orientation)
C) Medially only
D) Posteriorly only
Answer: B) Laterally and slightly anteriorly; inferior margin projects more medially (clinical orientation)

80. The Eustachian tube’s cartilaginous portion is supported by which muscle for active opening during swallowing?
A) Tensor tympani only
B) Tensor veli palatini (main opener) and levator veli palatini assist
C) Levator palpebrae superioris only
D) Stylopharyngeus only
Answer: B) Tensor veli palatini (main opener) and levator veli palatini assist

81. The term “conductive hearing loss” implies impairment of sound transmission in:
A) Inner ear only
B) External and/or middle ear (sound conduction pathway) with normal cochlear function
C) Central auditory pathways only
D) Brainstem auditory nuclei only
Answer: B) External and/or middle ear (sound conduction pathway) with normal cochlear function

82. The bony Fenestra vestibuli is closed by:
A) Round window membrane only
B) Stapes footplate at oval window (ovalis)
C) Tympanic membrane only
D) Cochlear aqueduct membrane only
Answer: B) Stapes footplate at oval window (ovalis)

83. The highest/most lateral part of the cochlear duct is near the:
A) Round window niche only
B) Scala vestibuli at the base — cochlear duct spirals between scala vestibuli and scala tympani
C) Oval window posterior margin only
D) Tympanic membrane
Answer: B) Scala vestibuli at the base — cochlear duct spirals between scala vestibuli and scala tympani

84. The tensor tympani dampens sounds produced by:
A) External speakers only
B) Chewing and self-generated sounds (via contraction pulling malleus medially)
C) Loud external explosions exclusively
D) Vestibular stimulation only
Answer: B) Chewing and self-generated sounds (via contraction pulling malleus medially)

85. The oval window communicates internally with the:
A) Scala tympani directly
B) Scala vestibuli (vestibule → scala vestibuli via oval window/transmission)
C) Cochlear aqueduct only
D) Eustachian tube only
Answer: B) Scala vestibuli (vestibule → scala vestibuli via oval window/transmission)

86. The minimal pressure required to move ossicular chain is reduced by:
A) Loss of ossicular chain only
B) Area ratio between tympanic membrane and stapes footplate (large TM area concentrated onto small footplate increases pressure) and lever action of ossicles
C) Closing of Eustachian tube permanently
D) Rigidity increase of stapes footplate only
Answer: B) Area ratio between tympanic membrane and stapes footplate (large TM area concentrated onto small footplate increases pressure) and lever action of ossicles

87. The middle ear epithelium is continuous with:
A) External auditory canal skin only
B) Mucosa of nasopharynx via Eustachian tube and respiratory epithelium
C) Periosteum of mastoid only
D) Endolymphatic sac epithelium only
Answer: B) Mucosa of nasopharynx via Eustachian tube and respiratory epithelium

88. The facial nerve canal’s dehiscence over the middle ear may expose the nerve to middle ear disease. The canal is located in which temporal bone part?
A) Squamous only
B) Petrous part of temporal bone (facial canal runs through petrous temporal bone)
C) Mastoid tip only
D) Styloid process only
Answer: B) Petrous part of temporal bone (facial canal runs through petrous temporal bone)

89. The external acoustic (auditory) meatus is approximately how long in adults?
A) 5–6 cm
B) 2.5–3.5 cm
C) 10 cm
D) 0.5 cm only
Answer: B) 2.5–3.5 cm

90. The auditory brainstem response (ABR) wave I originates from which structure?
A) Medial geniculate body
B) Distal portion of cochlear nerve near cochlea
C) Inferior colliculus only
D) Organ of Corti musculature
Answer: B) Distal portion of cochlear nerve near cochlea

91. The main drainage of middle ear lymph is to the:
A) Submandibular nodes only
B) Deep cervical nodes (especially superior deep cervical / jugulodigastric region)
C) Parotid nodes only
D) Preauricular nodes exclusively
Answer: B) Deep cervical nodes (especially superior deep cervical / jugulodigastric region)

92. A perilymph gush during stapedectomy indicates a lesion of:
A) Tympanic membrane only
B) Footplate/oval window breach causing perilymph leak
C) External auditory canal injury only
D) Ossicular chain continuity intact only
Answer: B) Footplate/oval window breach causing perilymph leak

93. A cochlear implant bypasses which structures to directly stimulate auditory nerve?
A) Outer ear only
B) Hair cells in organ of Corti (cochlea) by placing electrode array in scala tympani to stimulate spiral ganglion/cochlear nerve
C) Semicircular canals only
D) Middle ear mucosa only
Answer: B) Hair cells in organ of Corti (cochlea) by placing electrode array in scala tympani to stimulate spiral ganglion/cochlear nerve

94. The anterior tympanic artery supplying the middle ear region is a branch of:
A) Superficial temporal artery only
B) Maxillary artery (branch from 1st/2nd part variations)
C) Internal carotid directly only
D) Vertebral artery
Answer: B) Maxillary artery (branch from 1st/2nd part variations)

95. The cochlear duct is impermeable to perilymph-endolymph exchange primarily because of:
A) Reissner’s membrane and tight junctions in stria vascularis and cochlear duct epithelia
B) Tight junctions in Reissner’s membrane and ductal epithelium and stria vascularis barrier
C) Presence of ossicles only
D) Continuous vascular shunt only
Answer: B) Tight junctions in Reissner’s membrane and ductal epithelium and stria vascularis barrier

96. The posterior semicircular canal is most nearly in the same plane as the:
A) Superior canal only
B) Contralateral posterior canal (paired vertical plane)
C) Horizontal canal always
D) Cochlear duct only
Answer: B) Contralateral posterior canal (paired vertical plane)

97. The chorda tympani passes between which two middle ear ossicles?
A) Malleus and stapes
B) Between malleus handle (neck) and incus (long process) crossing middle ear cavity
C) Directly through stapes only
D) Lateral to tympanic membrane without crossing ossicles
Answer: B) Between malleus handle (neck) and incus (long process) crossing middle ear cavity

98. The otic (cochlear) nerve projects centrally to synapse first in which nucleus complex?
A) Superior olivary nucleus only
B) Cochlear nucleus (dorsal and ventral) at pontomedullary junction
C) Lateral geniculate nucleus only
D) Inferior olivary nucleus only
Answer: B) Cochlear nucleus (dorsal and ventral) at pontomedullary junction

99. The tympanosclerosis refers to:
A) Inflammatory tumor of middle ear mucosa
B) Calcification and scarring of tympanic membrane and middle ear leading to decreased mobility
C) Bacterial infection of mastoid tip only
D) Hyperplasia of ossicles that increases mobility
Answer: B) Calcification and scarring of tympanic membrane and middle ear leading to decreased mobility

100. The vestibular aqueduct contains which important structure?
A) Cochlear nerve only
B) Endolymphatic duct and sac (connects vestibule endolymph to endolymphatic sac in posterior cranial fossa)
C) Internal carotid artery
D) Pharyngotympanic tube only
Answer: B) Endolymphatic duct and sac (connects vestibule endolymph to endolymphatic sac in posterior cranial fossa)