NCERT Class 6 Science Chapter 11 Question Answer Nature’s Treasures

Answers to Questions from Chapter 11: Nature’s Treasures

Enhance Your Learning: Match, Classify, and Answer

1. Match the items with their jumbled-up names and classify them:

2. True or False Statements:

(i) Nature has all the resources to meet human needs. [T]
(ii) Machines are a resource found in nature. [F]
Correction: Machines are human-made resources.
(iii) Natural gas is a non-renewable resource. [T]
(iv) Air is a renewable resource. [T]

3. Fill in the blanks using the appropriate options:

(i) A fuel commonly used in two-wheelers like scooters or bikes is (b) Petrol.
(ii) An example of a renewable resource is (b) Water.

4. Classify the following as renewable or non-renewable resources:

• Renewable Resources: Forests.
• Non-Renewable Resources: Coal, Natural Gas, Minerals.

5. Why do we say that petroleum is a non-renewable resource?
Petroleum is a non-renewable resource because it takes millions of years to form from the remains of ancient organisms, and once depleted, it cannot be replenished within a human lifespan.

6. Why is it difficult to regrow forests?
Forests take decades or even centuries to grow back fully. They depend on suitable climatic conditions, soil fertility, and biodiversity. Large-scale deforestation disrupts ecosystems, making regeneration harder.

7. List five daily activities that use natural resources and suggest ways to reduce their use:

8. Four activities possible due to the presence of air:

1. Breathing for all living organisms.
2. Flying kites and gliders.
3. Pollination of plants through wind.
4. Generating energy via wind turbines.

9. How to enhance the green cover in your locality?

• Plant native trees and shrubs.
• Conduct awareness drives on afforestation.
• Encourage schools and communities to plant trees.
• Protect existing trees from being felled.
• Practice urban gardening on rooftops and balconies.

10. Questions on the energy used for cooking in the illustration:

(i) Type of energy: Solar energy.
(ii) Benefit: It is renewable and eco-friendly.
Drawback: It depends on sunlight availability and may not work efficiently on cloudy days.

11. How does cutting down trees impact soil quality?
Tree roots hold the soil together, preventing erosion. Without trees, soil loses nutrients and is washed away by wind and water, leading to land degradation.

12. Two ways human activities pollute the air and one solution:

• Pollution Causes:
  1. Burning fossil fuels releases harmful gases.
  2. Industrial emissions contribute to air pollution.
• Solution: Promote the use of electric vehicles and renewable energy sources.

13. What happens if there is no sunlight for a week?

• Solar panels will not generate electricity.
• Plants will stop photosynthesis, affecting the food chain.
• Dependence on non-renewable energy will increase.

14. Fill in the blanks with appropriate terms:

(i) Air is a renewable resource.
(ii) Petroleum is a non-renewable resource.
(iii) Fossil fuels are found in limited quantities.
(iv) Forests and water are examples of renewable resources.

15. Is large-scale tree felling justified?
No, it is not justified. Trees provide oxygen, prevent soil erosion, support biodiversity, and combat climate change. Cutting them for industries and housing disrupts ecosystems. Sustainable alternatives like reforestation and using eco-friendly materials should be adopted.

16. Propose a plan to use less water in your school:

• Install low-flow taps and sensors.
• Collect rainwater for gardening and cleaning.
• Fix water leaks promptly.
• Conduct awareness programs for students on water conservation.

Benefits: Saves water, reduces water bills, and instills responsible habits.

Learning Further

1. Rainwater harvesting techniques in India:

• Stepwells: Common in Rajasthan and Gujarat for storing rainwater.
• Check dams: Small barriers built across streams to hold water.
• Percolation pits: Used to recharge groundwater in rural areas.

2. Investigate the effects of air pollution on human health:

• Findings: Respiratory problems like asthma and bronchitis; long-term exposure causes cardiovascular issues.
• Practical Steps:
  • Create green belts around schools.
  • Ban burning of waste in the community.

3. Organize a tree plantation drive:

• Steps:
  • Identify locations for planting.
  • Arrange for saplings, tools, and volunteers.
  • Create awareness about the importance of trees.
  • Regularly water and maintain the saplings.

Sample Report:
Trees Planted: Neem, Banyan, Mango, Gulmohar, Peepal.
Importance: These trees provide shade, oxygen, fruits, and improve air quality.

Nature’s Treasures: Questions and Answers

1. What are natural resources?
Natural resources are materials or substances found in nature, such as air, water, soil, forests, rocks, minerals, and fossil fuels, that are essential for the survival of all living beings.

2. Why are natural resources important for survival?
Natural resources provide food, water, air, and energy, which are essential for the survival of all living beings and for maintaining life on Earth.

3. What is the composition of air?
Air is composed of 78% nitrogen, 21% oxygen, and 1% other gases like argon, carbon dioxide, and trace gases.

4. What is renewable energy?
Renewable energy is energy derived from resources that are replenished naturally, such as sunlight, wind, water, and biomass.

5. Give three examples of renewable resources.
Air, water, and forests.

6. What are non-renewable resources?
Non-renewable resources are those that exist in limited quantities and do not get replenished within a reasonable period, such as coal, petroleum, and natural gas.

7. Why is water considered a precious resource?
Water is essential for drinking, cooking, farming, and industrial processes. Freshwater is limited, making it a precious and scarce resource in many parts of the world.

8. What is rainwater harvesting?
Rainwater harvesting is the process of collecting and storing rainwater for later use, reducing dependence on other water sources.

9. What is the significance of forests?
Forests provide food, shelter, oxygen, and medicinal plants. They help regulate climate, prevent soil erosion, and support biodiversity.

10. What is the role of earthworms in soil?
Earthworms help loosen and aerate the soil, making it more fertile and suitable for plant growth.

11. What are fossil fuels?
Fossil fuels, such as coal, petroleum, and natural gas, are energy sources formed from the remains of ancient plants and microorganisms over millions of years.

12. Why should we conserve fossil fuels?
Fossil fuels are limited and their excessive use leads to air pollution and climate change. Conservation ensures their availability for future generations.

13. What are human-made resources?
Human-made resources are objects or tools created by humans using natural resources, such as solar panels, vehicles, and buildings.

14. How does the Sun act as the main source of energy?
The Sun provides heat and light, enabling plants to perform photosynthesis, which forms the basis of the food chain. It also drives the water cycle.

15. What is the purpose of the Chipko Movement?
The Chipko Movement aimed to protect forests from deforestation by encouraging people, especially women, to hug trees to prevent their felling.

16. How do plants recycle nutrients in soil?
Fallen leaves decompose into organic matter, enriching the soil with nutrients, which are then absorbed by plants for growth.

17. Why are windmills important?
Windmills convert wind energy into mechanical or electrical energy, providing a renewable and clean source of power.

18. What is the difference between rocks and minerals?
Rocks are made up of one or more minerals. Minerals are naturally occurring substances with a defined chemical composition.

19. What are the uses of rocks?
Rocks are used in construction, making tools, and as decorative items. Examples include marble, granite, and slate.

20. How are fossil fuels formed?
Fossil fuels are formed from the remains of dead plants and microorganisms that were buried under layers of earth and subjected to heat and pressure over millions of years.

21. What are the consequences of deforestation?
Deforestation leads to loss of biodiversity, climate change, soil erosion, and disruption of the water cycle.

22. Why is solar energy considered eco-friendly?
Solar energy is renewable, abundant, and does not cause pollution or emit greenhouse gases.

23. How does air pollution affect the environment?
Air pollution can cause respiratory diseases, harm wildlife, reduce crop yields, and contribute to global warming and acid rain.

24. What are stepwells, and why are they important?
Stepwells, like those in Rajasthan and Gujarat, are structures designed to store rainwater and water seepage. They are essential for water conservation in arid regions.

25. How does the water cycle help conserve water?
The water cycle ensures the continuous movement of water through evaporation, condensation, and precipitation, naturally replenishing water sources.

26. What is biodiversity?
Biodiversity refers to the variety of living organisms, including plants, animals, and microorganisms, in a particular environment.

27. What is the role of solar panels?
Solar panels capture sunlight and convert it into electricity, providing a sustainable and renewable energy source.

28. Why should we prevent water pollution?
Preventing water pollution ensures the availability of clean water for drinking, agriculture, and supporting aquatic life.

29. What are the consequences of overusing non-renewable resources?
Overusing non-renewable resources can lead to their depletion, energy crises, environmental degradation, and economic instability.

30. How can we conserve natural resources?
We can conserve natural resources by reducing waste, recycling materials, using renewable energy, practicing rainwater harvesting, and planting trees.