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Microbes in Human Welfare — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMicrobes in Human Welfare1 Mark
Question
Two statements are given-one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both assertion and reason are true and reason is the correct explanation of assertion.
  2. Both assertion and reason are true but reason is not the correct explanation of assertion.
  3. Assertion is true but reason is false.
  4. Both assertion and reason are false.
Assertion: Immobilised yeasts cause less fermentation.
Reason: Brewer's yeast produces beer not wine.
✓

Answer

  1. Both assertion and reason are false.

Solution:

In immobilised fermentation process, living yeast cells are immobilised in calcium alginate beads. The beads containing living cells are kept in columns in the fermentation tank. The technique allows quicker fermentation about 20 times as compared to batch process. The fermentation rapidly becomes vigorous with the evolution of large quantities of CO2. Different kinds of alcoholic beverages are produced by using different brewer's yeast and the fermenting medium. For example - (I) Beer is an undistilled product of grain-mesh fermentation brought about by Saccharomyces cerevisiae andS. carisbergensis, (II) wine is an undistilled product of fruit juice fermentation brought about by Saccharomyces eliipsoidens.

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