O-LevelBiologyRespiration5090/12 · Oct/Nov 2021 · Q271 Mark

What is the main role of yeast in the production of beers and wines?

Ato carry out aerobic respiration of sugar

Bto produce ethanol by fermentation

Cto release bubbles of carbon dioxide

Dto reduce the amount of sugar in the product

✓ Correct answer

B: to produce ethanol by fermentation

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Topic: Respiration, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source: O-Level Biology, Oct/Nov 2021 Paper 1 Variant 2, question 27.

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