When in the presence of sugar, yeast perform

"The chemical reaction between yeast and sugar produces ethanol and carbon dioxide. The balanced chemical equation for this reaction is glucose/sugar (C6H12O6) in the presence of the yeast enzyme zymase reacts to produce 2C2H5OH (ethanol) + 2CO2 (carbon dioxide). This is the ethanol fermentation process used to make beer, wine and bread."

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