Date | November 2020 | Marks available | 1 | Reference code | 20N.1.SL.TZ0.11 |
Level | Standard level | Paper | Paper 1 | Time zone | TZ0 / no time zone |
Command term | Question number | 11 | Adapted from | N/A |
Question
The diagram shows a respirometer.
[Source: Courtesy The Royal Society of Biology.]
What solution should be in the bottom of each tube and in which direction will the manometer fluid move?
Markscheme
B
Examiners report
This was another poorly answered question, but a reasonable discriminator. It was based on one of the prescribed practicals, so was not unfair. The even spread of answers reveals two gaps in understanding: that an alkali rather than an acid is needed to absorb carbon dioxide and also that the fluid in the manometer moves in the direction of the tube with the organisms, because oxygen is used up.