O-LevelBiologyRespiration5090/12 · May/June 2023 · Q151 Mark

When yeast cells respire anaerobically, which substance is used and which substances are produced?

Asubstance used: alcohol, substances produced: carbon dioxide and water

Bsubstance used: alcohol, substances produced: lactic acid and water

Csubstance used: sugar, substances produced: alcohol and carbon dioxide

Dsubstance used: sugar, substances produced: carbon dioxide and water

✓ Correct answer

C: substance used: sugar, substances produced: alcohol and carbon dioxide

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Topic: Respiration, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source: O-Level Biology, May/June 2023 Paper 1 Variant 2, question 15.

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