Biology Exam 1

Front 1

what are the two functions of the ear

Back 1

balance and hearing

Front 2

where is the center for balance and equilibrium

Back 2

the inner ear

Front 3

what are the organs of equilibrium

Back 3

interconnected canals and sacs--> labyrinth

Front 4

what are the two components of the vestibular apparatus?

Back 4

1. sacule and utricle
2. three semicircular canals

Front 5

where do i find the hair cells and what are their function?

Back 5

inner ear->labyrinth->sacule and utricle
1. sensory receptors
2. mechanoreceptors (pressure)
3. awareness of position relative to the ground

Front 6

where do i find the otolithes and what do they do?

Back 6

labbyrinth->sacule and utricle-> otoliths
Ear stones-they are grains of calcium carbonate
1. gavity reception
2. when head tilts, otoliths bend hairs

Front 7

what fills the semicircular canal?

Back 7

filled with endolymth fluid

Front 8

what is the ampulla?

Back 8

1. enlargements at the base of each canal
-head moves-->fluid moves in canal-->hairs im ampulla bend--> action potential happens

Front 9

what is the orientation of the ear canals and why is it important?

Back 9

each canal is at right angle to each other and it allows detection of turning in any direction

Front 10

frequency of wave

Back 10

# of pressure waves that occur in a second
slow fequency-low pitch
fast frequency- high pitch

Front 11

what is the significance of amplitude of a wave

Back 11

it is proportional to the loudness of a sound

Front 12

what are the three chambers of the ear?

Back 12

outer ear-pinna
middle ear-auditory bones
inner ear-cochlea

Front 13

how does the ear hear?

Back 13

1. sound enters outer ear
2. pinna leads to ear canal
3. ear canal collects waves and channels it to the tympanic membrane
4. tympanic membrane vibrates
5. vibration is transmitted to the middle ear
6. vibrations amplifies sound from the middle ear into the inner ear
7. oval window transmits info into inner ear
8. waves vibrate the basilar membrane
9. stereocilia(tips of hair cells) rub against tectorial membrane
10. action potential

Front 14

describe the structures of the middle ear

Back 14

1. air filled cavity
2. connects to the through via Eustachian tube
3. equalizes pressure btw middle ear and atmosphere
4. ossicles

Front 15

what are the 3 ossicles and what do they do?

Back 15

malleus- hammer
incus- anvil
stapes-stirrup

Front 16

what are the 3 chambers of the cochlear in the inner ear

Back 16

3 structures filled with fluid
1. vestibular canal
2. cochlear duct
3. tympanic canal
*basilar membrane separates cochlear duct from temp. canal

Front 17

how does the oval window transmit info

Back 17

1. bows in and out
2. pressure waves transmitted to fluid in the vestibular and tympanic canals
3. causes round windew to bow in and out
4. vibrates vasilar membrane

Front 18

what is the organ of corti and where is it located?

Back 18

ear->inner ear->cochlear duct->organ of corti
1. auditory organ
2. 18000 receptor cells
3. detects changes in pressure and waves
4. located between 2 membranes
5. hairs rest of basilar membrene
6. tectorial membran is stiff and doesnt vibrate much

Front 19

how is the auditory nerve formed?

Back 19

axons joined to form cochlear nerves which join to form the auditory nerve to the brain

Front 20

what does the basilar membrane do?

Back 20

allows the brain to interprate different sound sound pitches.
1. stiff and narrow end- high pitches
2. wide and flexible end- low pitches