"Conservation of Plants and Animals" for Class 8 Science (CBSE):-
Extra 20 important long questions and answers from the chapter:5
1. What is deforestation? List its causes.
Ans: Deforestation is the large-scale cutting of trees and clearing of forests for various purposes.
Causes of Deforestation:
Agriculture expansion – Forests are cleared for farming.
Urbanization – More land is needed for roads and buildings.
Industrialization – Setting up factories requires land.
Forest fires – Accidental or natural fires destroy trees.
Grazing of animals – Overgrazing damages vegetation.
2. Explain the consequences of deforestation.
Ans: Deforestation has severe effects on the environment.
Effects of Deforestation:
Loss of biodiversity – Many species lose their habitat.
Soil erosion – Without trees, soil is easily washed away.
Climate change – Increased carbon dioxide levels lead to global warming.
Decreased rainfall – Trees help in cloud formation and rainfall.
Desertification – Continuous deforestation can turn fertile land into deserts.
3. What is a biosphere reserve? Mention its importance.
Ans: A biosphere reserve is a protected area that preserves wildlife, plants, and human communities while promoting sustainable use of resources.
Importance of Biosphere Reserves:
Conserve biodiversity – Protects plant and animal species.
Maintains ecological balance – Helps in climate regulation.
Supports research and education – Scientists study biodiversity.
Encourages sustainable use of natural resources – Promotes eco-friendly activities.
Protects endangered species – Helps prevent species extinction.
4. What are wildlife sanctuaries? Mention their functions.
Ans: Wildlife sanctuaries are protected areas where animals live in their natural habitat with minimal human interference.
Functions of Wildlife Sanctuaries:
Provide a safe habitat for animals.
Protect endangered species from poaching.
Allow limited human activities like eco-tourism.
Preserve genetic diversity of wildlife.
Maintain ecological balance in nature.
5. Define national parks. How are they important for conservation?
Ans: National parks are protected areas where animals, plants, and natural resources are conserved in their natural habitat.
Importance of National Parks:
Protects endangered species like tigers, elephants, etc.
Preserves natural landscapes and forests.
Restricts human activities such as hunting and poaching.
Promotes tourism and environmental education.
Supports scientific research and biodiversity conservation.
6. What are endangered species? Give examples.
Ans: Endangered species are those animals and plants that are at risk of extinction due to habitat loss, poaching, or environmental changes.
Examples:
Bengal Tiger
Indian Rhino
Snow Leopard
Olive Ridley Turtle
Great Indian Bustard
7. What is an extinct species? Give examples.
Ans: Extinct species are those that no longer exist due to environmental changes or human activities.
Examples:
Dodo
Passenger Pigeon
Woolly Mammoth
Tasmanian Tiger
Pink-headed Duck
8. What are endemic species? Give examples.
Ans: Endemic species are species found only in a particular geographical region and nowhere else in the world.
Examples:
Lion-tailed macaque (Western Ghats)
Nilgiri Tahr (Western Ghats)
Malabar Civet (India)
Andaman Wild Pig (Andaman Islands)
Kashmir Stag (India)
9. What is afforestation? How does it help in conservation?
Ans: Afforestation is the process of planting trees in deforested areas to restore forests.
Benefits of Afforestation:
Prevents soil erosion by holding the soil together.
Increases oxygen production and reduces CO₂.
Restores wildlife habitats for animals and birds.
Reduces global warming by absorbing greenhouse gases.
Improves rainfall by increasing moisture levels.
10. What is Project Tiger? What is its significance?
Ans: Project Tiger was launched in 1973 by the Government of India to protect and increase the population of tigers.
Significance:
Protects Bengal Tigers from extinction.
Preserves forest ecosystems.
Reduces poaching and illegal wildlife trade.
Creates awareness about tiger conservation.
Improves tourism and research opportunities.
11. What are the different types of protected areas for wildlife conservation? Explain each.
Ans: There are four types of protected areas for wildlife conservation:
Biosphere Reserves – Large areas that protect biodiversity and allow human activities in certain regions.
National Parks – Strictly protected areas where no human activities like hunting or grazing are allowed.
Wildlife Sanctuaries – Areas where animals are protected, but limited human activities like tourism and grazing may be allowed.
Zoos – Captive environments where animals are kept in enclosures for public awareness and conservation programs.
Botanical Gardens – Protected areas where plants are grown and conserved for research.
Seed Banks – Facilities that store seeds of different plant species for future conservation.
Marine Reserves – Areas where aquatic life is protected from fishing and industrial activities.
12. How does deforestation lead to loss of biodiversity?
Ans: Deforestation is one of the main causes of biodiversity loss due to:
Habitat destruction – Animals and plants lose their natural home, leading to extinction.
Disruption of food chains – When trees and plants are removed, herbivores suffer, which affects the entire ecosystem.
Soil erosion – Without tree roots, soil washes away, making it hard for plants to grow.
Climate change – Trees absorb carbon dioxide; cutting them increases greenhouse gases and raises global temperatures.
Reduction in rainfall – Trees release moisture, so their removal leads to lower rainfall.
Increased human-wildlife conflict – Animals lose their habitat and enter human settlements in search of food.
Loss of medicinal plants – Many medicinal plants grow in forests and are lost due to deforestation.
13. How can the government and individuals work together to conserve wildlife?
Ans: The government and individuals can take the following steps:
Government laws and policies – Enforcing strict wildlife protection laws and banning poaching.
Creating more national parks and sanctuaries – Expanding protected areas to safeguard species.
Educating people – Schools, campaigns, and social media can raise awareness about conservation.
Afforestation programs – Both the government and individuals should plant more trees.
Reducing pollution – Preventing water and air pollution helps maintain habitats.
Sustainable resource use – Encouraging eco-friendly products to reduce deforestation.
Animal rescue and rehabilitation – Setting up centres to treat injured or endangered animals.
14. Explain the effects of poaching on wildlife and the environment.
Ans: Poaching refers to the illegal hunting of animals for their skin, horns, bones, or other body parts.
Leads to extinction of species – Many animals like the Bengal tiger and rhino are at risk due to poaching.
Disrupts food chains – Removing predators or prey from the ecosystem affects biodiversity.
Encourages illegal wildlife trade – Smuggling of ivory, tiger skins, and rhino horns fuels illegal markets.
Reduces biodiversity – The loss of one species affects many others.
Damages tourism and economy – Wildlife tourism is affected when species become rare or extinct.
Promotes human-wildlife conflict – As animal numbers decrease, surviving animals may enter human settlements.
Weakens genetic diversity – Killing the strongest animals in a species reduces its ability to adapt to changes.
15. How does forest conservation help in maintaining the water cycle?
Ans: Forests play a crucial role in maintaining the water cycle in the following ways:
Transpiration process – Trees release water vapor, which helps in cloud formation and rainfall.
Prevents water runoff – Tree roots absorb and store rainwater, reducing floods.
Recharges groundwater levels – Forests help maintain underground water tables.
Regulates humidity – Forests keep the atmosphere moist, which affects regional weather.
Reduces soil erosion – Tree roots hold soil in place, preventing loss of fertile land.
Maintains river ecosystems – Forests near rivers protect aquatic life by preventing pollution.
Supports plant and animal life – Water availability helps sustain diverse ecosystems.
16. What steps can be taken to prevent desertification?
Ans: Desertification is the process where fertile land turns into desert due to deforestation and climate change. It can be prevented by:
Planting trees (afforestation and reforestation) – Helps bind the soil and prevent erosion.
Adopting sustainable farming practices – Avoid overgrazing and use crop rotation.
Water conservation techniques – Rainwater harvesting and drip irrigation reduce water wastage.
Restricting deforestation – Forest laws should be enforced to protect green cover.
Reducing pollution – Less air and soil pollution means healthier land.
Using organic fertilizers – Prevents chemical damage to soil.
Restoring degraded lands – Governments should rehabilitate affected areas.
17. What is the role of forests in controlling air pollution?
Ans: Forests play an essential role in reducing air pollution by:
Absorbing carbon dioxide – Trees take in CO₂ and help reduce global warming.
Releasing oxygen – Producing fresh air for humans and animals.
Filtering pollutants – Leaves and branches trap dust and harmful gases.
Cooling the environment – Trees provide shade and regulate temperature.
Reducing noise pollution – Dense forests act as sound barriers.
Improving humidity levels – More trees lead to better moisture retention in the air.
Supporting biodiversity – Clean air benefits all living organisms.
18. How does conservation of biodiversity benefit humans?
Ans: Biodiversity conservation is crucial for human survival because:
Provides food and medicine – Many plants and animals are sources of medicine and food.
Maintains ecological balance – Prevents species extinction and ecosystem collapse.
Reduces climate change impact – Forests absorb greenhouse gases.
Improves water and air quality – Biodiversity ensures clean resources.
Supports agriculture – Natural pollinators like bees help in crop production.
Promotes tourism – Wildlife tourism generates revenue and jobs.
Cultural and spiritual value – Many species and ecosystems hold religious and cultural significance.
19. Why are seed banks important for plant conservation?
Ans: Seed banks store seeds of various plants to preserve biodiversity and ensure future food security.
Prevents extinction of plant species – Rare plants can be reintroduced.
Preserves genetic diversity – Different plant varieties are stored for research.
Helps farmers – Provides seeds during droughts or disasters.
Supports reforestation programs – Seeds help regrow forests.
Aids in scientific research – Helps study plant evolution and disease resistance.
Maintains food security – Protects crop varieties from climate change.
Useful for future generations – Acts as a backup against biodiversity loss.
20. What are the human activities that harm biodiversity?
Ans: Human activities that harm biodiversity include:
Deforestation – Cutting trees destroys habitats.
Pollution – Air, water, and soil pollution harm living organisms.
Poaching – Illegal hunting of animals reduces wildlife populations.
Overfishing – Depletes marine biodiversity.
Urbanization – Construction damages ecosystems.
Introduction of invasive species – Non-native species disrupt food chains.
Climate change – Global warming affects species' survival.
