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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: Aspergillus niger produces lactic acid.
Reason: Rhizopus produces citric acid.
✓

Answer

  1. Assertion is true but reason is false.

Solution:

Citric acid is obtained through the fermentation carried out by Aspergillus niger and Mucor species on sugary syrups. Lactic acid was the first organic acid to be produced from the microbial fermentation. Lactic acid fermentation is carried out by both bacteria (e.g. Streptococcus la dis, Lactobacillus species and fungi (e.g. Rhizopusi.

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