Ears 1

Question 1

Sense of hearing =

Answer 1

Audition
Detects sound
Perceives and interprets nuances in sounds
The majority of our auditory cortex is dedicated to processing the sounds of human speech
There are 30 different gene mutations that cause deafness

Question 2

Sense of balance =

Answer 2

Vestibular system
Head and body location
Head and body movements
Head and body equilibrium

Question 3

sound

Answer 3

results from movement of air molecules in a particular wave pattern.

Question 4

Sound waves vary in:

Answer 4

wavelength
frequency
amplitude

Question 5

wavelength

Answer 5

Wavelength, length from compression to compression

Question 6

frequency

Answer 6

or Frequency, which determines pitch (highness or lowness).

Question 7

amplitude

Answer 7

Amplitude, height or difference in pressure between compressions and rarefactions, which determines loudness (intensity of the sound).

Question 8

pitch

Answer 8

Audible Range is 20 Hz to 20,000 Hz
Range decreases with age especially higher frequencies.
High pitch = high frequency, short wavelength
Low pitch = low frequency, long wavelength

Question 9

intensity

Answer 9

Range 0 db to 200 db
High intensity (larger amplitude) louder 
Low intensity softer

Question 10

timbre

Answer 10

complexity,

characteristic quality

Question 11

infrasound

Answer 11

Sounds lower than 20 Hz = infrasound

Elephants (14-16 Hz) & Whales (as low as 7 Hz)

Question 12

ultrasound

Answer 12

Sounds greater than 20,000 Hz (20kHz) = ultrasound
Bats (100 kHz)
Dolphins & their fish prey (180 kHz)

Question 13

loudness of sound and what causes hearing loss

Answer 13

The loudness of a sound is measured in decibels. Constant noise above 90 decibels can cause permanent hearing loss.

Question 14

pinna/auricle

Answer 14

external ear; funnels sound into auditory canal, especially from the front

Question 15

auditory canal

Answer 15

Sound waves travel to tympanic membrane, lined with cerumen (ear wax)
Ends at outer layer of ear drum

Question 16

Tympanic Membrane –

Answer 16

Sound waves vibrate it; sound passed to ossicles

Question 17

ossicles

Answer 17

bones in the air filled tympanic cavity, malleus (hammer), incus (anvil) and stapes (stirrup) – pass along and amplify sounds

Question 18

eustachian tube

Answer 18

connects ear to nasopharynx, equalizes air pressure and drains mucus from middle ear.
Ends at the Oval window of Cochlea

Question 19

middle ear parts

Answer 19

Tympanic Membrane –
Ossicles –
Eustachian Tube –

Question 20

outer ear parts

Answer 20

pinna and auditory canal

Question 21

eustahcian tube extra

Answer 21

Valve normally closed
Unequal pressure between middle ear and outside air is painful (Ex. On airplane)
Actively open valve to equalize pressure (Ex. Yawning, swallowing)

Question 22

ear infections from eustachian tube

Answer 22

Ear Infections: bacteria and viruses enter from throat, membranes become swollen, trap fluid, pressure on eardrum, mainly under age 7, tympanostomy tube in eardrum to equalize pressure, will drop out over time.

Question 23

ossicles extra

Answer 23

Amplifies vibrations of tympanic membrane around 20 fold because more pressure needed to vibrate the fluid in the cochlea. Pressure increases: due to ossicles acting like levers to increase the force on the oval window and the surface area of the oval window is smaller than the tympanic membrane.

Question 24

damage where can cause conduction deafness (one area)

Answer 24

ossicles

Question 25

attenuation reflex

Answer 25

muscles (tensor tympani, stapedius) contract to make bones rigid with loud noises to reduce sound conduction and protect the inner ear, delay of 50-100 msec. Reduces loud sounds that would saturate receptors, increasing the range we can hear. Suppresses low frequencies more than high frequencies so can discern voices in a noisy environment. Helps prevent us from hearing our own voices too loudly when we speak.