| Date | May 2012 | Marks available | 1 | Reference code | 12M.1.HL.TZ2.5 |
| Level | Higher level | Paper | Paper 1 | Time zone | Time zone 2 |
| Command term | State | Question number | 5 | Adapted from | N/A |
Question
What is the approximate thickness of the plasma membrane of a cell?
A. 10 nm
B. 50 nm
C. 10 µm
D. 50 µm
Markscheme
A
Examiners report
Only half of candidates knew that the thickness of a plasma membrane is about 10nm, with large numbers instead choosing the answer 10µm. More emphasis therefore needs to be given to the difference between micrometres and nanometres.
