Test your extensive knowledge of biodiversity, its patterns, importance, loss, and conservation strategies as covered in the 'Biodiversity and Conservation' chapter. This comprehensive set of multiple-choice questions is designed for competitive exam preparation.
Test Your Knowledge
Showing questions 21 - 40 of 47
21. Which of the following recent extinctions is **incorrectly** matched with its region of occurrence?
Recent extinctions include the **Steller’s Sea Cow (Russia)**, not the Atlantic Ocean.
22. Which group of animals appears to be more vulnerable to extinction, as noted by ecologists?
Careful analysis of records shows that extinctions across taxa are not random; some groups like **amphibians appear to be more vulnerable to extinction**.
23. Currently, what percentage of all bird species, mammal species, amphibian species, and gymnosperm species worldwide face the threat of extinction, respectively?
Presently, **12 per cent of all bird species, 23 per cent of all mammal species, 32 per cent of all amphibian species and 31 per cent of all gymnosperm species** in the world face the threat of extinction.
24. How does the current 'Sixth Extinction' differ from the five previous episodes of mass extinction in Earth's history?
The difference is in the rates; the **current species extinction rates are estimated to be 100 to 1,000 times faster than in the pre-human times and our activities are responsible for the faster rates**.
25. What is the 'sobriquet' used to describe the four major causes of accelerated rates of species extinctions?
There are four major causes (‘**The Evil Quartet**’ is the sobriquet used to describe them).
26. Which of the following is considered the **most important cause** driving animals and plants to extinction?
**Habitat loss and fragmentation** is the most important cause driving animals and plants to extinction.
27. Tropical rain forests, once covering more than 14 percent of the Earth's land surface, now cover no more than what percentage?
Tropical rain forests **once covering more than 14 per cent of the earth’s land surface**, these rain forests **now cover no more than 6 per cent**.
28. The Amazon rain forest is often called the 'lungs of the planet'. For what primary human activities is it being cut and cleared?
The Amazon rain forest is being cut and cleared for **cultivating soya beans or for conversion to grasslands for raising beef cattle**.
29. Which of the following species extinctions in the last 500 years were primarily due to over-exploitation by humans?
Many species extinctions in the last 500 years (**Steller’s sea cow, passenger pigeon**) were due to overexploitation by humans.
30. The introduction of the Nile perch into Lake Victoria in East Africa led to the extinction of what type of indigenous species?
The Nile perch introduced into Lake Victoria in east Africa led eventually to the extinction of an ecologically unique assemblage of **more than 200 species of cichlid fish** in the lake.
31. Which of the following are examples of invasive weed species posing a threat to native species in India?
The sources mention **carrot grass (Parthenium), Lantana and water hyacinth (Eicchornia)** as invasive weed species.
32. When a species becomes extinct, the plant and animal species associated with it in an obligatory way also become extinct. This phenomenon is known as:
**Co-extinctions** occur when a species becomes extinct, and its obligatorily associated species (like parasites with their host, or a pollinator with its coevolved plant) also face extinction.
33. Which of the following falls under the 'narrowly utilitarian' argument for conserving biodiversity?
The **narrowly utilitarian arguments** are based on the direct economic benefits humans derive from nature, such as food, firewood, fibre, construction material, industrial products, and **medicinal importance**.
34. What percentage of drugs currently sold in the market worldwide are derived from plants?
**More than 25 per cent of the drugs currently sold in the market worldwide are derived from plants**.
35. The 'broadly utilitarian' argument for conserving biodiversity highlights the major role biodiversity plays in ecosystem services. Which of the following is an example of an ecosystem service mentioned?
The broadly utilitarian argument says that biodiversity plays a major role in many **ecosystem services**, such as the Amazon forest producing 20% of total oxygen and **pollination by pollinators like bees, bumblebees, birds and bats**.
36. Which of the following best describes the 'ethical argument' for conserving biodiversity?
The **ethical argument** relates to what we owe to other species, recognizing that every species has an intrinsic value, and we have a moral duty to care for their well-being and pass on our biological legacy to future generations.
37. When an entire ecosystem is conserved to protect its biodiversity at all levels, for example, saving a forest to save a tiger, what type of conservation approach is this called?
When we conserve and protect the whole ecosystem, its biodiversity at all levels is protected - this approach is called **in situ (on site) conservation**.
38. Initially, how many 'biodiversity hotspots' were identified globally, and what is the current total number after more were added?
**Initially 25 biodiversity hotspots were identified but subsequently nine more have been added to the list, bringing the total number of biodiversity hotspots in the world to 34**.
39. Which of the following are the three biodiversity hotspots that cover India’s exceptionally high biodiversity regions?
Three of these hotspots – **Western Ghats and Sri Lanka, Indo-Burma and Himalaya** – cover our country’s exceptionally high biodiversity regions.
40. Despite covering less than 2 percent of the Earth's land area, what significant impact could strict protection of biodiversity hotspots have on ongoing mass extinctions?
Although all the biodiversity hotspots put together cover less than 2 per cent of the earth’s land area, the number of species they collectively harbour is extremely high and strict protection of these hotspots could **reduce the ongoing mass extinctions by almost 30 per cent**.