Botany MCQs for NEET — Practice Questions with Answers

A keystone species is the one which has a very prominent effect in the ecosystem it inhabits. They play a very important role in determining the structure, number and types of several other species in the ecosystem.

For example- Jaguar is a predator which feeds on more than 80 different species of animals and thus control the balance in forest ecosystem.

Biodiversity hotspots’ are the regions with very high levels of species richness and high degree of endemism(threatened species) that is, species confined to that region and not found anywhere else.

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The species-area relationship states that the number of species found in a given area increases as the area increases. This is because larger areas tend to have more diverse habitats and resources, allowing for a greater variety of species to thrive.

The exotic species introduced in India which caused the environmental damage and posed threat to native species are weed species like carrot grass (Parthenium), Lantana and water hyacinth (Eicchornia). The recent illegal introduction of the African catfish Clarias gariepinus for aquaculture purposes is posing a threat to the indigenous catfishes in our rivers.

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Habitat loss and fragmentation is the most important cause driving animals and plants to extinction. The most dramatic examples of habitat loss come from tropical rainforests.

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Although India has only 2.4 per cent of the world’s land area, its share of the global species diversity is 8.1 percent.

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The organism which facing very high risk of extinction in the wild is considered as critically endangered species by International Union for Conservation of Nature (IUCN). Critically endangered species are Great Indian Bustard, Red headed Vulture.

Introduction

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Biodiversity and Conservation

15.1 Biodiversity

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Biodiversity and Conservation

15.1 Biodiversity

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Biodiversity and Conservation