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Organisms and Populations — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations1 Mark
MCQ
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.
Assertion : No two species can occupy the same ecological niche in a habitat.
Reason : A habitat can contain only one ecological niche.
  • A
    Both assertion and reason are true and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true but reason is not the correct explanation of assertion.
  • ✓
    Assertion is true but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: C.
Assertion is true but reason is false.
The place where an organism lives is called its habitat. Habitats are characterised by conspicuous physical features, which may include the dominant forms of plant and animal life.
Habitat may also refer to the place occupied by an entire biological conununity.
For example, a large number of species are found in a forest habitat. On the other hand, the ecological niche of an organism represents $(i)$ the range of conditions it can tolerate $(ii)$ the resources it utilises, and $(iii)$ its functional role in the ecological system.
A habitat can contain many ecological niches and support a variety of species. Each species has a distinct niche, and no two species are believed to occupy exactly the same niche.

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