Ear 1

Question 1

External Ear

Answer 1

• Pinna (collects/conducts sound)
• Tympanic membrane
• External auditory canal
  – hair follicles (sebaceous/ceremonious gland = earwax)

Question 2

Middle Ear

Answer 2

• air filled space
• bones (malleus, incus, stapes)
• Eustachian tube (connects to nasopharynx)

Question 3

Inner Ear

Answer 3

• auditory + vestibular nerve
• auditory system = cochlea
• vestibular system = sacs and canals

Question 4

Two types of labyriths

Answer 4

Bony – perilymph
Membranous – endolymph

Question 5

Vestibular system

Answer 5

Superior/posterior/horizontal semi circular duct
– rotational movement
– ampulla + crista ampullaris

Saccule and Utricle (sacs)
– linear acceleration
– each have macula

Question 6

Crista Ampullaris

Answer 6

• crista, cupula (gelatinous cap), hair + supporting cells
• head rotates = semicircular canals move, endolymph lags behind b/c inertia (deflects cupula, + stereocilia)
• angular acceleration

Question 7

Maculae

Answer 7

• otholiths (crystals) – heavier than endolymph deflect stereocilia
• glycoprotein layer (hair + supporting cells)
• linear acceleration + gravitational pull