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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: Acetic acid is prepared by acetic acid bacteria.
Reason: Alcoholic fermentation and the conversion of alcohol to acetic acid are aerobic processes.
✓

Answer

  1. Assertion is true but reason is false.

Solution:

Acetic acid is prepared from fermented alcohols with the help of acetic acid bacteria, Acetobacter acetobacter aceti. Alcoholic fermentation is anaerobic process but the conversion of alcohol to acetic acid is aerobic one.

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