| Date | November 2012 | Marks available | 1 | Reference code | 12N.3.SL.TZ0.13 |
| Level | Standard level | Paper | Paper 3 | Time zone | TZ0 |
| Command term | List | Question number | 13 | Adapted from | N/A |
Question
Explain how sound is perceived by the ear.
Hearing is a result of the stimulation of mechanoreceptors. List three other main types of receptors.
1. ..................................................................
2. ..................................................................
3. ..................................................................
Markscheme
sound (waves) vibrate eardrum/tympanic membrane;
movement is magnified by ossicles/middle ear bones;
oval window vibrates / fluid in cochlea moves and moves hairs in cochlea;
different frequencies detected by different parts of cochlea membrane and hair cells;
these are connected to the auditory nerve;
chemoreceptors / photoreceptors / thermoreceptors / baroreceptors
Award [1] for three correct receptors.
Examiners report
Most candidates were able to gain at least 2 marks and many 3 marks in (e) for explaining sound perception by the ear.
Many candidates were able to list three other types of receptors for the mark in (f).
