Ear

Question 1

The inner ear contains three (3) distinct sensory structures.

Identify these & their primary functions (3) [x5]

Answer 1

Organ of Corti (detection of sound waves)

Macula (static equilibrium),

Crista Ampullaris (dynamic equilibrium/acceleration & deceleration)

Question 2

Identify the type of receptor cell that is common to the above sensory structures (½) [x5]

Answer 2

Hair cells

Question 3

Name the cranial nerve that conveys the sensory stimuli from the above sensory structures to the brain (½)

Answer 3

CN VIII

Question 4

Outline the how differences in pitch (frequency) of sound waves are detected in the cochlea of the inner ear & name the sensory structure & cell type involved in detection of acoustic stimuli (3)

Answer 4

Tonotopic organization of the cochlea - low frequencies excite cells at apex of cochlea, high frequencies at the basis. Organ of Corti, Hair cells