Some sugar solution is taken in a test-tube and a little of substance X in powder form is added to it. The mouth of test-tube is closed with a cork and allowed to stand for sometime. On opening the cork, a characteristic smell of substance Y is obtained and a gas Z is also observed to be formed. The gas Z extinguishes a burning matchstick.(a) What could be (i) X, (ii) Y, and (iii) Z ?(b) What is the process of converting sugar into substance Y by the action of X known as ?(c) What type of respiration is exhibited by X in the above process ?
(a) (i) X is yeast (ii) Y is ethanol (iii) Z is carbon dioxide.
(b) Fermentation.
(c) X exhibits the anaerobic respiration.
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