Date | November 2016 | Marks available | 2 | Reference code | 16N.3.SL.TZ0.4 |
Level | Standard level | Paper | Paper 3 | Time zone | TZ0 / no time zone |
Command term | Describe | Question number | 4 | Adapted from | N/A |
Question
To test hearing, sounds are played at very low volume levels and gradually increased until the patient can hear the sound. This is repeated with different frequencies which correspond to low or high pitch sounds. The results are marked on an audiogram. This audiogram is from a 60-year-old woman.
Human speech occurs at a volume of approximately 60 dB and at frequencies between 125 Hz and 4000 Hz. Outline whether the woman would hear all conversations with both ears.
The woman suffers from otosclerosis in the right ear, a condition where the bones of the middle ear do not function properly. Describe how this is consistent with the hearing test result shown in the audiogram.
Explain the role of the hair cells in the cochlea.
Markscheme
left ear would hear everything but the right ear would not «at higher frequencies»
OR
cannot hear all high frequencies of speech (with both ears)
Allow numerical responses in support of the answer.
a. the bones in the middle ear amplify/make sounds louder
b. the audiogram shows the woman needs louder sounds to hear with her right ear
Allow vice versa.
Could use data to support answer.
a. sounds/vibrations make the fluid/liquid in the cochlea move/vibrate
b. amount of movement is proportional to the amplitude /loudness/ of the sound OWTTE.
c. amount of movement is proportional to the frequency/wavelength/pitch
d. hair cells located within organ of Corti
e. (hair cells have) nerve cells connected to auditory nerve
OR
nerve cells transmit impulses to brain