Hearing

Question 1

What is in the External Ear

Answer 1

Auricle (pinna)
External Auditory Canal
Ear Drum (Tympanic Membrane)

Question 2

What is in the Middle Ear?

Answer 2

Auditory Ossicles (malleus, incus, stapes)
Oval window
Round window
Tensor tympani & stapedius muscles

Question 3

What is in the Inner ear

Answer 3

Bony & Membranous Labyinth

• semicircular canals
• vestibule
• cochlea

Auditory Appartus
Vestibulocochlear Nerve (CN8)

Question 4

What is the Spiral Organ of Corti and describe it

Answer 4

It is in the auditory apparatus

• it is the sensory receptor for hearing
• contains hair cells embedded between tectoral (stationary) and basilar membranes (move in response to vibrations)

Question 5

What is the path of sound?

Answer 5

Sound waves strikes ear drum —>ossicles move, causing vibrations of membrane at opening of upper chamber (amplifying sound) —> continue through the windows —> movement of fluid in upper chamber —> vibration of vascular membrane and attached hair cells —> hairs bend because the tips are embedded in the immobile tectorial membrane (DEPOLARIZATION) —> Cochlear nerve endings activated —> CN 8 pathways