Audition-Signal Transduction

Question 1

sound

Answer 1

waves of compressed and rarefied air

Question 2

pitch

Answer 2

how high or low the sounds is, determined by frequency of a sound wave, measured in Hz = cycles/sec

Question 3

volume/intensity

Answer 3

describes the loudness, determined by amplitude of a sound wave, measured in decibels

Question 4

how does sound move through the air?

Answer 4

pinna, auditory canal, tympanic membrane, ossicles, cochlea

Question 5

windows in cochlea

Answer 5

oval window: where stapes pounds on cochlea to make vibrations in the liquid

round window: whwere fluid causes buldging out at the end of the cochlea

Question 6

characteristics of the base and apex of cochlea’s basilar membrane

Answer 6

base: narrower, stiffer, vibrates more in response to high frequnecies
apex: wider, floppier, vibrates more in response to low frequnecies

Question 7

structure of cochlea

Answer 7

Question 8

converting sound into a neuronal signal

Answer 8

sound waves in cochlea move basilar membrane which smooshes tectorial membrane onto hair cells. hair cells detect the amount of smooshing

Question 9

depolarization in hair cells

Answer 9

at rest some K+ channels are open. When basalar membrane pushed down, opens more channels through tip links, lots of K+ flow in, big depolarization. when basalar membrane pushed up, channels close, hyperpolarization. sound pressure and basilar membrane have opposite movement. membrane potential mimics sound pressure waves.

Question 10

amplification of sound

Answer 10

one inner cell goes to many sprial ganglion cells. outer hair cells have motor proteins that activated when the cell is depolarized and cause contraction to increase the movement of the basilar layer