Ear Part 2

Question 1

What is the frequency of perceived sound determined by?

Answer 1

By which part of the cochlear duct is stimulated the most

Question 2

What is intensity of perceived sound determined by?

Answer 2

It’s determined by the number of hair cells stimulated in that location

Question 3

What does sound consist of?

Answer 3

Waves of pressure through a medium such as water or air

Question 4

What do pressure waves consist of ?

Answer 4

Regions where air molecules are crowded together and adjacent zones are where molecules are farther apart

Question 5

What are Sine waves?

Answer 5

S shaped curves that travel the air at about 1235km/h

Question 6

What is a wavelength?

Answer 6

Distance between two adjacent troughs/crests and inversely related to the frequency

Question 7

What is frequency?

Answer 7

The number of waves that pass the reference point in a given period of time

Question 8

What is the pitch of sound?

Answer 8

Our sensory response to frequency of sound (the higher the frequency the shorter the wavelength)

Question 9

What is sound energy reported in?

Answer 9

Decibels

Question 10

What is amplitude?

Answer 10

It’s the intensity of sound

Question 11

What is the process of hearing?

Answer 11

The sound wave arrives at the tympanic membrane, as it enters the external acoustic meatus and the orientation of the auditory canal provides directional sensitivity
When the tympanic membrane moves it displaces the auditory ossicles and the tympanic vibrates also causing the ossicles to vibrate and this is how sound is amplified

Question 12

What happens when the stapes moves inward?

Answer 12

The basilar membrane distorts towards the round window and it is pushed outwards and thats how sound is processed and bulges into the middle ear cavity

Question 13

What happens when the stapes moves outward?

Answer 13

The basilar membrane rebounds and the oval window is distorted and the round window moves inwards and dissipates excess energy to the cochlear fluid

Question 14

What happens when there is movement of the stapes at the oval window?

Answer 14

It creates pressure waves in the perilymph of the Scala vestibular as liquids aren’t compressible

Question 15

What do the inner hair cells of the organ of Corti do?

Answer 15

They convert slund vibrations to neural signals through the steering action of their stereocillia

Question 16

What do the outer hair cells do?

Answer 16

They function as acoustic pre amplifiers which improve frequency selectivity by allowing the organ of Corti to become attuned to specific frequencies

Question 17

What do pressure waves do?

Answer 17

They distort the basilar membrane on their way to the round window of the scalar tympani

Question 18

What does vibration of the basilar membrane cause?

Answer 18

It causes vibration of hair cells against the tectorial membrane

Question 19

Where is information relayed?

Answer 19

It is carried by the cochlear branch of the cranial nerve VII to the cochlear nuclei of the medulla oblongata to other centers of the brain

Question 20

What is signal generation?

Answer 20

When the basilar membrane moved upwards and reticular membrane and sterocillia bends outwards and produces a receptor Potential this depolarization allows for CA to enter which in turn results in the release of NT The NT will stimulate the sensory neuron auditory fibers to send signals to CNS

Question 21

Which nerve is cranial nerve VII?

Answer 21

The Vestibulocochlear nerve

Question 22

What Is the auditory pathway?

Answer 22

Where stimulation of hair cells with activate sensory neurons which cell bodies are in the adjacent spiral ganglion and the affarent fibers of the neurons from the cochlea branch VII
The axons enter the medulla and synapse at the dorsal and ventral cochlear nuclei and the information will cross to the opposite side if the brain and move up to the inferior colliculus of the midbrain

Question 23

Where do ascending auditory sensations synapse?

Answer 23

Medial geniculate nucleus of the thalamus

Question 24

What are effects of aging on the ear?

Answer 24

The typanic membrane gets less flexible
Articulations between the ossicles stiffen and the round window May begin to ossify

Question 25

What are the 3 types of hearing loss?

Answer 25

Conductive
Sensorineural
Mixed

Question 26

What is conduction deafness?

Answer 26

When there is a wax build up or damage to the eardrum

Question 27

What is sensorineural deafness?

Answer 27

Age or noise related damage to the cochlea and degeneration of the cochlea nerve

Question 28

What Is mixed deafness?

Answer 28

Combination of sensorineural and conductive