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Biodiversity and Conservation — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYBiodiversity and Conservation1 Mark
Question
For 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: There are 36 biodiversity hotspots in the world.
Reason: High level of species richness is a criteria for selection of a biodiversity hotspot.
✓

Answer

  1. Both assertion and reason are true but reason is not the correct explanation of assertion.

Explanation:

Hotspots are areas with high density of biodiversity or megadiversity which are also the most threatened ones. Ecologically hotspots are determined by four factors.

  1. Number of specieslspecies diversity.
  2. Degree of endemism.
  3. Degree of threat to habitat due to its degradation and fragmentation.
  4. Degree of exploitation.

Myers (1988) initially identified 12 hotspots. Today the number of hotspots identified by ecologists is 36.

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