Question 19M.3.SL.TZ1.6
| Date | May 2019 | Marks available | [Maximum mark: 7] | Reference code | 19M.3.SL.TZ1.6 |
| Level | SL | Paper | 3 | Time zone | TZ1 |
| Command term | Annotate, Identify, Outline, State | Question number | 6 | Adapted from | N/A |
The diagram illustrates the sensitivity to sound frequencies, measured in Hz, of the different regions of the semicircular canal. The base is the region closest to the oval window.
[Source: © International Baccalaureate Organization 2019]
Outline the relationship between the distance from the oval window and the sound frequency detected.
[1]
the further from the base, the lower the frequency detected ✔
Allow vice versa
Most answered correctly.
State the range of sound frequencies detected by the ear.
[1]
20 000 Hz «20 kHz» to 20 Hz ✔
Unit required. Allow 19 980 Hz.
The correct frequency range was given but the unit was often omitted.
Sensory receptors are divided into different categories. Hair cells in the cochlea are sensory receptors. State the category to which they belong.
[1]
mechanoreceptor ✔
Perhaps a third of candidates gave the correct term.
The diagram shows the human ear.
[Source: Didier Descouens, https://commons.wikimedia.org/wiki/Category:Human_middle_ear#/media/File:Place-desosselets-
Schema.jpg, licensed under CC BY-SA 3.0]
Identify the structure labelled Y in the diagram.
[1]
auditory/cochlear/acoustic nerve ✔
Most correct answers were for auditory nerve rather than the alternatives.
Annotate the diagram with an X to show the internal location where a cochlear implant is placed.
[1]
cochlea annotated with an X ✔
eg:
[Source: Didier Descouens, https://commons.wikimedia.org/wiki/Category:Human_middle_ear#/media/File:Place-desosselets-
Schema.jpg, licensed under CC BY-SA 3.0]
X can be anywhere in the spiral of the cochlea
Most candidates placed the X in the correct region.
Outline the function of the stapes.
[2]
a. connects the oval window to the eardrum/ossicles ✔
b. mechanical transmission of vibration of eardrum
OR
amplify vibration/sound ✔
c. moves oval window with frequency of the vibration/sound
OR
transmits vibration/sound to inner ear/cochlea ✔
There were some good answers here, although connections to parts of the ear were sometimes confused. Amplification and transmission to the cochlear were frequent responses
