CUET Categorised PYQ Biology Unit 13

Statement B is correct because the tropical Amazon rainforest in South America is considered the most biodiverse region on Earth. Statement D is correct because tropical regions are less seasonal and experience relatively stable environmental conditions, promoting species diversification.

Endemism refers to species that are naturally confined to a specific geographical area. It is a pattern of biodiversity and not a factor responsible for biodiversity loss. Co-extinction, over-exploitation and alien species invasions are among the major causes of biodiversity loss.

Insects constitute the most species-rich group among animals. More than 70% of all recorded animal species belong to insects.

Amazon rainforest is the most species-rich terrestrial ecosystem on Earth. It contains millions of plant, animal and microbial species and represents the highest biodiversity among major biomes.

Relict vegetation represents genetic diversity. Amphibian variety in Western Ghats indicates species diversity. Mangroves and coral reefs represent ecological diversity. Extinction of Dodo signifies biodiversity loss.

The term biodiversity was popularized by Edward Wilson to describe diversity at genetic, species and ecosystem levels of biological organization.

Cryopreservation preserves biological materials outside their natural habitat under extremely low temperatures. Therefore, it is an ex-situ conservation method.

Eichhornia crassipes (water hyacinth) grows rapidly and covers entire water surfaces, reducing oxygen availability and harming aquatic life. Hence it is called the "Terror of Bengal."

Paul Ehrlich proposed the Rivet Popper Hypothesis. He compared species in an ecosystem to rivets in an aircraft. Loss of a few rivets may not immediately affect the plane, but continued loss can eventually cause collapse. Similarly, continuous species loss can destabilize ecosystems.

Botanical gardens maintain plant species outside their natural habitats and therefore represent ex-situ conservation.

Seed banks store seeds under controlled conditions outside their natural habitats. Hence they are an example of ex-situ conservation.

Correct matching: A. Dodo → Mauritius B. Quagga → Africa C. Thylacine → Australia D. Steller's Sea Cow → Russia These are standard NCERT examples of extinct species.

Ex situ conservation involves protecting species outside their natural habitats. Wildlife safari parks maintain animals in protected and managed environments away from their original ecosystems. These facilities help conserve endangered species and support breeding programs.

In situ conservation protects species in their natural habitats. National parks, wildlife sanctuaries and biosphere reserves preserve organisms where they naturally occur. Zoological parks maintain animals outside their natural habitats and therefore represent ex situ conservation.

Narrowly utilitarian arguments include direct benefits obtained from biodiversity such as medicines, fuel, food, industrial products and construction materials. Pollination is an ecological service provided by biodiversity and falls under broadly utilitarian values.

Tropical regions show high biodiversity because they receive more solar energy, are less seasonal, and have remained relatively undisturbed over long evolutionary periods. Frequent glaciations disrupt ecosystems and reduce opportunities for continuous evolution and speciation.

Paleontological evidence shows that Earth has undergone five major mass extinction events since life diversified. These events eliminated large numbers of species and significantly influenced the course of evolution.

India is represented in three major biodiversity hotspots: Western Ghats–Sri Lanka Indo-Burma Himalaya The Amazon forests are located in South America and do not include any Indian biodiversity region.