Nature's Treasures — Class 6 Science
Curiosity · Chapter 11
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5- Mathematics
- Science
- + 3 more
- Space weighted by chapter size
- Charts from the book's own data
- Traps corrected
- Space weighted by chapter size
- Charts from the book's own data
- Traps corrected
- Space weighted by chapter size
- Charts from the book's own data
- Traps corrected
- Space weighted by chapter size
- Charts from the book's own data
- Traps corrected
- Space weighted by chapter size
- Charts from the book's own data
- Traps corrected
Chapter summary
Key ideas & terms
- Natural resources
- Resources we get from nature, such as air, water, sunlight, forests, soil, rocks, minerals, and fossil fuels.
- Composition of air
- Air is a mixture of about 78% nitrogen, 21% oxygen, and 1% argon, carbon dioxide, and other gases.
- Rainwater harvesting
- The collection and storage of rainwater for later use, an age-old Indian practice seen in structures like the bawadi and vav.
- Fossil fuels
- Coal, petroleum, and natural gas, formed over millions of years from buried remains of organisms and plants, and used as fuels.
- Renewable resources
- Resources that get renewed or replenished by natural processes within a reasonable period, such as air, water, and forests.
- Non-renewable resources
- Resources present in limited amounts that are not replenished within a reasonable period, such as minerals, soil, rocks, and fossil fuels.
Extra questions & answers
What is the composition of air?
Air is a mixture of gases containing about 78% nitrogen, 21% oxygen, and 1% argon, carbon dioxide, and other gases.
Why is oxygen in the air important?
Oxygen is needed by the body to perform its functions, and most living beings need oxygen for their survival; we cannot survive without it for even a few minutes.
Why must water be conserved even though it covers most of the Earth?
Because most of the Earth's water is salty seawater unfit for use, and only a small fraction of accessible freshwater is available for our needs.
What is rainwater harvesting?
Rainwater harvesting is the collection and storage of rainwater for later use; it is an age-old Indian practice seen in structures such as the bawadi in Rajasthan and the vav in Gujarat.
Why is the Sun called the main source of energy on Earth?
Because plants use sunlight to make food, on which animals depend, and the Sun also drives climate, seasons, weather, and the water cycle, sustaining life on Earth.
How are rocks and minerals related?
Rocks are made up of minerals, and important metals such as aluminium, gold, copper, and iron are extracted from these minerals.
What are fossil fuels, and how are they formed?
Fossil fuels are coal, petroleum, and natural gas, formed over millions of years from the remains of microorganisms and plants buried deep inside the Earth.
What is the difference between renewable and non-renewable resources?
Renewable resources are renewed by natural processes within a reasonable time, such as air, water, and forests, while non-renewable resources are not, such as minerals and fossil fuels.
Why is petroleum considered a non-renewable resource?
Because petroleum takes millions of years to form and exists in limited quantities, so it cannot be replenished within a reasonable period once it is used up.
Why should forests be preserved?
Forests provide food, shelter, and many products, protect the soil, and support biodiversity, yet take many years to regrow, so they must be used responsibly to allow regeneration.
Let us enhance our learning
1. Fig. 11.9 shows items related to natural resources. Match them with their jumbled up names. Make another table and write the names of these resources. Classify these resources as renewable or non-renewable. ocrk
Unjumbled word is rock. Rock is a non-renewable resource because it takes thousands to millions of years to form and cannot be replenished within a human lifetime.
1. Fig. 11.9 shows items related to natural resources. Match them with their jumbled up names. Make another table and write the names of these resources. Classify these resources as renewable or non-renewable. refost
Unjumbled word is forest. Forest is a renewable resource because it can regrow and be replenished naturally within a reasonable time if used responsibly, although it takes many years to fully regenerate.
1. Fig. 11.9 shows items related to natural resources. Match them with their jumbled up names. Make another table and write the names of these resources. Classify these resources as renewable or non-renewable. ndiw
Unjumbled word is wind. Wind is a renewable resource because it is generated continuously by natural processes and will not get exhausted.
1. Fig. 11.9 shows items related to natural resources. Match them with their jumbled up names. Make another table and write the names of these resources. Classify these resources as renewable or non-renewable. atwre
Unjumbled word is water. Water is a renewable resource because it is replenished continuously through the water cycle, although fresh water available for use is limited and must be conserved.
2. State whether the following statements are True [T] or False [F]. If False, correct them. (i) Nature has all the resources to meet human needs. [ ]
True. Nature provides resources like air, water, sunlight, soil and forests that meet our basic needs for survival, though we must use them wisely and not waste them.
2. State whether the following statements are True [T] or False [F]. If False, correct them. (ii) Machines are a resource found in nature. [ ]
False. Machines are not found in nature. They are human-made resources created by people using natural resources. Corrected statement: Machines are human-made resources.
2. State whether the following statements are True [T] or False [F]. If False, correct them. (iii) Natural gas is a non-renewable resource. [ ]
True. Natural gas is a fossil fuel formed over millions of years from buried remains, found in limited quantities and not replenished quickly, so it is non-renewable.
2. State whether the following statements are True [T] or False [F]. If False, correct them. (iv) Air is a renewable resource. [ ]
True. Air is a renewable resource because it is naturally replenished and will not get exhausted if kept clean.
3. Fill in the blanks using the most appropriate option— (i) A fuel that is commonly used in two wheelers like scooters or bikes is......... (a) Kerosene (b) Petrol (c) Diesel (d) LPG
(b) Petrol. Most scooters and motorbikes run on petrol obtained from petroleum.
3. Fill in the blanks using the most appropriate option— (ii) An example of a renewable resource is .................. (a) Coal (b) Water (c) Natural gas (d) Petrol
(b) Water. Water is replenished by the water cycle and is renewable, while coal, natural gas and petrol are fossil fuels and non-renewable.
4. Classify the following as renewable or non-renewable resources—coal, natural gas, forests and minerals.
Renewable: forests. Non-renewable: coal, natural gas and minerals. Coal and natural gas are fossil fuels formed over millions of years and minerals and rocks also take a very long time to form, so they are not replenished quickly. Forests can regrow naturally within a reasonable period if conserved.
5. Why do we say that petroleum is a non-renewable resource?
Petroleum is called non-renewable because it is formed from the remains of microorganisms and plants buried deep inside the Earth over millions of years. It is found in limited quantities and once used it gets exhausted and cannot be formed again within a reasonable time for human use.
6. It is difficult to regrow forests. Justify this statement.
Forests are difficult to regrow because they contain a large variety of herbs, shrubs and trees along with many animals and micro-organisms that have developed together over many years. Cutting them destroys soil, biodiversity and habitats. It takes many years, proper climate, soil and protection for a new forest to grow back to its original diversity.
7. Make a list of five daily activities in which you use natural resources. Suggest ways by which you can reduce their use.
Five daily activities: 1) Drinking and cooking - uses water - turn off taps, fix leaks, use required amount only. 2) Travelling to school by bus or bike - uses petrol/diesel - walk, cycle or use public transport when possible. 3) Studying with books and furniture - uses forest wood and paper - use both sides of paper, repair furniture, plant trees. 4) Using electricity for lights and fans - uses coal and solar energy - switch off lights when not needed, use sunlight in daytime. 5) Eating food - uses soil, water and sunlight to grow crops - avoid wasting food, eat seasonal food.
8. List four activities that are possible due to the presence of air.
Four activities possible due to air: 1) Breathing by humans, animals and plants which need oxygen to live. 2) Flying of birds, insects and aeroplanes and blowing of wind that rotates a firki and windmills to generate electricity. 3) Burning of fuels for cooking and generation of heat and light which needs oxygen. 4) Hearing sounds and feeling breeze, and plants exchanging gases for photosynthesis.
9. How can you contribute towards enhancing the green cover of your locality? Make a list of actions to be taken.
Actions to enhance green cover: 1) Participate in Van Mahotsav and plant native trees and care for them. 2) Protect existing trees and not pluck leaves or cut branches unnecessarily. 3) Create a small garden at home or school and compost fallen leaves. 4) Spread awareness among friends and family about importance of trees for air, soil and shelter. 5) Water young plants regularly and avoid wasting paper to reduce demand for wood.
10. In the given illustration, we see that food is being cooked. Answer the following questions— (i) What type of energy is being used for cooking?
Solar energy is being used for cooking. The illustration shows a solar cooker which captures heat and light from the Sun to cook food.
10. In the given illustration, we see that food is being cooked. Answer the following questions— (ii) Name one benefit and one drawback of using this type of energy for cooking.
Benefit: Solar energy is renewable, free, clean and does not produce smoke or air pollution, and it saves fossil fuels. Drawback: It depends on sunlight, so it cannot be used at night, on cloudy days, or when the Sun is not visible, and cooking can be slower than with gas or electricity.
11. Cutting down trees on a large scale impacts the quality of the soil. Why do you think it is so?
Trees hold soil with their roots and prevent it from being washed away by water and wind. Fallen leaves decay and add nutrients to make soil fertile. When trees are cut on a large scale, soil becomes loose, loses nutrients, gets eroded easily and becomes less fertile, so it cannot support new plants well.
12. Explain two ways in which human activities pollute the air. Propose one action which can help in reducing air pollution.
Two ways humans pollute air: 1) Burning fossil fuels like petrol, diesel and coal in vehicles and factories produces smoke and carbon dioxide and other gases. 2) Dumping waste, burning trash and industrial smoke release harmful gases and particles into air. One action to reduce it: Use public transport, cycle or walk for short distances, and use cleaner fuels like CNG or electric vehicles, and plant more trees which purify air.
13. A family uses solar panels to generate electricity, a gas stove to cook food and a windmill for pumping water from a well. What would happen if there were no sunlight for a week?
If there is no sunlight for a week, solar panels will not generate electricity, so lights and appliances depending on them will not work and the family will need alternative sources like stored electricity or grid power. The gas stove will still work because it uses LPG or natural gas, and the windmill will still work if wind blows. However plants will make less food, clothes will not dry quickly, and overall life will be affected as the Sun is the main source of energy.
14. Fill up the blanks using the following terms— (fossil fuels, forest, air, petroleum, coal, water and non-renewable resource)
Natural Resources are divided into Renewable Resources and Non-renewable Resources. Examples of Renewable Resources are forest, air and water. Examples of Non-renewable Resources are fossil fuels which include petroleum, coal and natural gas. Natural gas, petroleum and coal are all fossil fuels and are non-renewable resources.
15. There is an increasing demand of trees to meet the requirements of industries and for housing. Therefore, trees are being felled. Is it justified? Discuss and prepare a brief report.
Cutting trees only to meet increasing demand is not justified if done without limits. Trees give us wood, paper and shelter but also give oxygen, hold soil, provide home to animals, control climate and maintain water cycle. Large-scale felling leads to loss of biodiversity, soil erosion, air pollution and climate change. A balanced report would say we should use wood responsibly, recycle paper, plant more trees than we cut, use alternatives like engineered wood, and protect forests through laws and movements like Chipko. Development is needed but must be sustainable.
16. Propose a plan to use less water in your school. What steps would you take to make this plan happen and how would it help the environment?
Plan to use less water in school: 1) Fix leaking taps and install low-water taps. 2) Turn off taps while soaping hands or brushing. 3) Use water from hand washing to water garden plants and practice rainwater harvesting. 4) Make duty chart for students to monitor water use and put posters about saving water. 5) Repair overflowing tanks and use buckets instead of hose for cleaning. Steps to make it happen: Form eco-club, get permission from principal, conduct awareness assembly, assign monitors, check monthly water meter. This will save precious fresh water, reduce wastage, keep water sources clean for all living beings and teach everyone to conserve water.