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Biodiversity and Conservation — BIOLOGY STD 12 Science — Question

Gujarat 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: Non-native or exotic species are often introduced in a region for their economic uses.
Reason: Exotic species are considered to be a major cause of extinction of indigenous species.
✓

Answer

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

Explanation:

The world is facing accelerated rates of species extinctions, largely due to human interference. There are four major causes  - (i) habitat loss and fragmentation, (ii) over-exploitation, (iii) alien species invasions and (iv) co-extinctions.

Non-native or alien species are often introduced inadvertently for their economic and other uses. They often become invasive and drive away the local species. The exotic species are considered to be second major cause of extinction of species (the first being habitat destruction).

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