O-LevelBiologyRespiration5090/11 · May/June 2023 · Q361 Mark

The diagram shows some apparatus set up to produce alcohol by fermentation. What is the purpose of the layer of oil?

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Ato keep the alcohol in the solution

Bto prevent aerobic respiration

Cto produce carbon dioxide

Dto provide nutrients for the yeast

✓ Correct answer

B: to prevent aerobic respiration

Oracle Prep sorts past-paper questions by topic, so you can drill Respiration and see which topics are most likely to come up next.

Topic: Respiration, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source: O-Level Biology, May/June 2023 Paper 1 Variant 1, question 36.

Questions and mark schemes are from past examination papers and remain the copyright of the exam board. How Oracle Prep builds its content