VERY SHORT ANSWER TYPE QUESTIONS (1 Mark)
Q1. What is a natural resource?
Ans.: All the material we obtain from nature and use it is called natural resource.
Q2. Name two important natural resources.
Ans.: Forest, Water, Wildlife.
Q3. What are 3 R’s used to save environment?
Ans. Reduce, Recycle and Reuse.
Q4. Define biodiversity.
Ans. The number of species found in an area is called biodiversity.
Q5. Name the bacteria whose presence in the water indicates its contamination with disease causing microbes.
Ans. Coliform bacteria.
Q6. Why fossil fuels should be used judiciously?
Ans. It is because these resources are limited, non-renewable and polluting.
Q7. State 2 advantages of constructing dam across a river.
Ans. It helps in generating electricity in irrigation.
Q8. Name the place where “Chipko Andolan” organised.
Ans. Reni Village in Garhwal.
Q9. Who started the “Chipko Movement”?
Ans. Sunderlal Bahuguna.
Q10. Name the main constituents of coal and petroleum.
Ans. Carbon, nitrogen, hydrogen, sulphur.
Q11. Name the gas responsible for global warming.
Ans. Carbon dioxide and methane.
Q12. State two disadvantages of constructing dam.
Ans. It can cause earthquakes, loss of habitat, submerging of plants releases methane gas
that causes green house effect.
Q13. Name any one stake holder.
Ans. Bishnoi community in Rajasthan.
Q14. Name two dam projects which are facing criticism.
Ans. Tehri dam on river Ganga and Sardar Sarovar dam on river Narmada.
Q15. What are the products formed when coal and petroleum are burnt?
Ans. Carbon dioxide, water, oxides of nitrogen and oxides of sulphur.
SHORT ANSWER TYPE QUESTIONS (2 or 3 Marks)
Q1. Why do we need to use our resources carefully?
Ans. It is because these resources are limited and the human population is increasing at very fast rate, the demand for these resources is increasing. For long term usage and to preserve them we need to use our resources carefully.
Q2. How does mining cause pollution?
Ans. Mining causes pollution because if produces large amount of slag which is discarded for every tonne of metal that is extracted.
Q3. Why are forests called as biodiversity hot spots?
Ans. Biodiversity hot-spot means a place where large number of species are found. The range of different life forms i.e., bacteria, fungi, ferns, flowering plants, variety of animals likes, insects, birds, reptiles, aves, mammals etc are all found in the forest.
Q4. For the conservation of forest who can be a stakeholder.
Ans. (i) The people who live in or around forest.
(ii) The forest department of the government.
(iii) The industrialists.
(iv) The wildlife and nature enthusiasts who want to conserve nature.
Q5. Prejudice against the traditional use of forest areas has no basis. Comment.
Ans. It can be explained with one example—The great Himalayan Park contain alpine meadows which were grazed by sheep in summer. Nomadic shepherds drove their flock up from the valley every summer. When the National Park was formed this practice was banned. Because of no grazing, the grass first grew very tall and then fell over on the ground preventing fresh growth. Hence the traditional use was helpful for the forest maintenance.
Q6. Name two industries based on forest produce.
Ans. Paper industries, bamboo, bidi and tendu leaves industries.
Q7. Why is it necessary to conserve forest and wildlife?
Ans. To preserve forest, maintain balance in the eco-system, prevent floods, droughts.
Q8. What is water harvesting? What is the main purpose of water harvesting?
Ans. Rain water harvesting is collecting the rain water, allowing it to percolate, discharge
down the earth and increase the ground water level. It is done to manage water.
Q9. Name the products of combustion of coal and petroleum. How do they effect our environment?
Ans. CO2, H2O, oxides of sulphur and nitrogen are released from the combustion of coal and petroleum.
Effect on environment:
(i) CO2 — Green house effect, global warming.
(ii) Oxides of sulphur and nitrogen causes acid rain.
Q10. A tribe is living near the forest. Name two things which they will commonly use from forest.
Ans. Tribe will use timber, firewood, fruits, gum, medicines from the forest.
Q11. Give an example of people’s participation in the management of forests.
Ans. Saving of sal forest of Arabari in Midnapore District.
Chipko Movement to protect the trees from cutting down in Reni village Garhwal.
Q12. Write two advantages of classifying sources as renewable and non-renewable.
Ans. Classification of resources helps us in deciding the kind of resource we should use judiciously and wisely. The resource that is not limited. It also helps us to know the importance of using renewable source of energy.
Q13. Which is better—recycle or reuse? Give example.
Ans. Reuse is better because recycling needs extra energy.
E.g., the glass containers in which we get jam, pickles etc., can be reused at home to keep kitchen stuff but if it goes for recycling then lot of energy and money is spent on recycling it and getting a new bottle.
Q14. Explain 3R’s with one example each.
Ans. Reduce—Less use of products like paper, clothes, plastic, wood, coal, petroleum so that it is not exploited from the nature.
Recycle—To make new items from the used articles like plastic, paper, wood, glass etc.
Reuse—Use the same thing again and again. E.g., use the jam and pickle containers for keeping kitchen stuff etc.
Q15. Give three changes you will make to stop or lower the use of coal and petroleum.
Ans. (i) Switch off lights when not required, and use CFL bulbs.
(ii) Not to use petrol fuel vehicles instead opt for CNG.
(iii) Use cycle or walk to go short distances.
Q16. What are the advantages of water stored in ground?
Ans. (i) Does not evaporate.
(ii) Recharges wells.
(iii) No danger of mosquito breeding.
(iv) Better availability of potable water.
Q17. Inspite of plenty rainfall in monsoon in some areas of India, there is failure to sustain water availability. Give reasons.
Ans. (i) Loss of forest cover prevents rainwater from seeping down the ground.
(ii) Underground water is not recharged.
Q18. What are three basic cause that has brought criticisms about large dams projects?
Ans. (i) Social problem—as its construction displaces large number of tribals and local peasants without proper compensation and rehabilitation.
(ii) Economic problem—such projects need lot of money for the setup or construction without much of out-put or benefit.
(iii) Environmental problem—the construction causes deforestration and loss of biological diversity.
Q19. Give three main uses of fossil fuels.
Ans. (a) Fossil fuels are used for generating electricity i.e., Coal is used in thermal power
plants on large scale to produce electricity.
(b) Coal and petroleum is also used in industries to prepare goods from raw-materials.
(c) Petroleum is used for transportation. In vehicles petrol or diesel is used.
Q20. List two traditional system of water harvesting. [CBSE 2008 F]
Ans. Khadim, tanks and nadis in Rajasthan, bandharas and tals in Maharashtra.
Q21. List four changes you would incorporate in your life style in a move towards sustainable use of available resources [AI CBSE 2008, 2009]
Ans. (i) Taking a bus, using cycle or walking.
(ii) Using CFL at home and switching off lights when not required.
(iii) Using the stairs instead of lift.
(iv) Wearing an extra sweater on cold days instead of encouraging the use of heaters.
Q22. State two reasons each of conserving [AI CBSE 2008]
(a) Forest and (b) Wild life
Ans. (a) Forest: It needs to be conserved as it is a natural resource, many industries depend on it and will exploit and deplete the forest. It is biodiversity hot-spot.
(b) Wildlife: It maintains the ecological balance. Hence all animals which are hunted for skin, fur, tusk, horns etc. need protection and their habitat also need to be conserved.
Q23. What are natural resources? State two factors that work against an equitable distribution of these resources. [CBSE 2009]
Ans. The resources obtained from the earth and which are naturally occuring are called natural resources.
Two factors which works against an equitable distribution of these resources are:
(i) Materialisation and (ii) Energisation
Q24. Why must we conserve our forests? List any two causes for deforestation taking place. [CBSE 2009]
Ans. We must conserve our forest as they are very useful.
(i) It conserves soil by preventing soil erosion, prevents flood and holds lot of water,
maintain ground level of water and brings rainfall.
(ii) It provides lot of raw material for many industries like timber, sal, wood, bidi,
tendu leaves, coir etc.
Two causes of deforestation:
(a) Exploitation by industries.
(b) Due to increase in population, lot of forest land is converted to build roads
and dams for the infrastructure development. Pressure of human settlement
is also a major cause.
Q25. What is Chipko Movement? Why should we conserve forests? [AI CBSE 2009]
Ans. It is the movement initiated by local people in the Reni Village of Garhwal by preventing the cutting down of trees by hugging the trees. It was initiated by Sunder Lal Bahuguna to stop the commercial exploitation of forest.
We should conserve forest because it is of great benefit to us as it holds soil, water, prevents floods, brings rain fall, maintain ecological balance on the earth.
Q26. An environmentalist on visit to your school suggested the use of three R’s to save the environment. Explain what he meant by three R’s and how you would follow his advice at home. [AI CBSE 2009]
Ans. The 3R’s to save the environment means:
(i) Reduce—It means we should use less resources. The demand of exploiting
resources should be reduced by switching off lights, fans when not required, by
not wasting paper, pencil etc.
(ii) Recycle—It means, to make new products from the old, used ones, e.g., recycle
used paper, plastic bags, glass material and metals like tins, cans, foils etc.
(iii) Reuse—It is the best option i.e., use the things, materials again and again. e.g.,
use the envelope which was already used, make use of plastic bottles, jam and
pickle containers etc.
Q27. List four advantage of water harvesting. [AI CBSE 2009]
Ans. Water harvesting is useful because
(i) It provides water for potable use.
(ii) It provides water for irrigation.
(iii) It provides water for recharging underground water reservoir.
(iv) It provides water for vegetation to grow.
Q28. How do advantages of exploiting natural resources with short-term aims differ from the advantages of managing our resources with a long-term perspective? [CBSE 2009 F]
Ans. Exploitation of natural resources with short-term aims means exploiting it for need, money and make them extinct but using the same resources with a long-term perspective means managing the resources wisely, judiciously and using them in such a manner that they are present for future generations to come i.e., sustainable management.
Q29. What is wild life? How is wild life important for us? [CBSE 2009 F]
Ans. Wild life means all the animals and plants that grow and live in forest, grow naturally, are not cultivated, domesticated and tamed.
Importance of wildlife:
(i) They help in maintaining ecological balance.
(ii) They provide aesthetic value for human beings.
Q30. What is water harvesting? Write any two advantages of it. [CBSE 2009 F]
Ans. Water harvesting means capturing water to recharge water reservoirs.
Benefits of water harvesting:
(i) It provides water for potable use.
(ii) It provides water for irrigation.
(iii) It increases the ground water level.
(iv) It provides water for the growth of vegetation.
Q31. List any two causes of our failure to sustain availability of underground water. [CBSE 2009]
Ans. Two causes which led to the failure of sustaining the availability of underground water are:
(i) Population: With the increase in population the demand is also increasing which is depleting the underground water.
(ii) Industrialisation: As the industries need more water to manufacture its goods, this led to decrease in the level of underground water.
LONG ANSWER TYPE QUESTIONS (5 Marks)
Q1. What are fossil fuels? How are they formed? Why should we use them judiciously?
Ans. Fossil fuels are obtained from the remains of plants and animals which got burried under the earth some millions of year ago. They changed into fuel due to tremendous heat and pressure.
The fossil fuels should be used judiciously because they are non-renewable resources, and can not be made again. It releases harmful and polluting gases like CO2, which causes green house effect and oxides of nitrogen and sulphur which causes acid rain.
Q2. What is sustainable development? Explain it with respect to forest, wildlife and water resources.
Ans. The proper management of natural resources using it wisely and judiciously so that it is available for the coming generations also. All these resources are maintained.
The population is increasing, demand for these resources is also increasing but they are limited in nature.
The management would prevent the exploitation of these resources and keep them available for future generations.
Forest—Many industries like timber, wood bidi, tendu leaves etc are dependent on the trees in the forest. They keep cutting the trees for use. This need to be managed properly and checked that new plantation of trees take place, animals are not harmed and are preserved.
Wildlife—All animals in the forest are disturbed due to the intervention of people into the forest. They are also killed for trade of skin, fur, tusk horn etc. If the animals in the forest are not managed and taken care of then they will be extinct which will disturb the ecological balance of the earth.
Water Resources—The main water resources are rivers, lake, ponds, underground water. The sources of water are getting polluted and the underground water is also discharged, used and the level of water is declining. Hence the recharge of water under the ground by rain water harvesting is necessary.
Q3. What is rain water harvesting? How can it be done at local level? What are its benefits?
Ans. Rain water harvesting is the indigenous water saving methods to capture every trickle of water that had fallen on land. For this we need to dig small pits and lakes, build small earthen dams, construct dykes, sand and lime stone reservoirs, set up roof top water collecting units. This will recharge ground water levels and bring rivers back to life.
Water harvesting techniques give people control over their local water resources, ensures,that the mismanagement and over exploitation of these resources is reduced/removed. The advantage of water stored in the ground are many. It does not evaporate, but spreads out to recharge wells and provide moisture for vegetation over a wide area.
It does not provide breeding area for mosquitoes. It is also protected from contamination by human and animal waste.
Q4. Dams are constructed on the river for multipurpose use give its advantages and
Ans. Advantages of dams:
(i) The water stored in the dams is used for irrigation by constructing canals which
carry water to the fields.
The Indira Gandhi Canal carries water from Bhakra dam Punjab to villages in Rajasthan desert where it has brought greenery and added life to the soil.
(ii) The water in dams is continuously available for the people in the vicinity to make use of it after purification.
(iii) The water of dam is also used in producing electricity. The water in dam that falls from a certain height gains kinetic energy and rotates turbines to generate electricity. Hence this way it makes hydroelectricity.
Disadvantages of dams:
(i) Social Problems: Due to dam’s construction large number of human settlements are submerged in water, many people become homeless. Govt. must provide adequate compensation for the rehabilitation of these people which is not being done.
(ii) Ecological problems: Lot of deforestration takes place for the construction of dams, which leads to loss of biodiversity. Many plants get submerged under water and on decomposition this releases methane gas; that is the greenhouse gas; causing global warming.
(iii) Economic problems: For the construction of dams large funds are required, Govt. invests lot of money in its construction and the benefits or the output is not equivalent.
Q1. Pritam stays in a village near a forest. He plays the best role of being a stakeholder of the forest by taking care of it, reporting on illegal cutting down of trees and forest fire etc.
(a) Name two industries based on forest produce.
(b) Give two causes of forest depletion in India.
(c) What values are reflected in Pritam?
Ans. (a) Paper, timber.
(b) Deforestation and forest fires.
(c) Pritam shows the values of personal responsibility and participating citizenship.
Q2. Arjun’s father dropped him to school every day in his car but when he learnt about the pollution he started using school transport thereafter.
(a) Give two disadvantages of using fossil fuel.
(b) Why should we use these resources wisely and judiciously?
(c) What value of Arjun is reflected?
Ans. (a) Two disadvantages of using fossil fuels are: It causes pollution and it is expensive
resource which cannot be replenished.
(b) These resources are limited and take long time in formation.
(c) Arjun is showing responsible behaviour and self-discipline.
Q3. Today we encounter the problem of water shortage, although it rains well in rainy season.
‘Khushi society’ has made a provision of rainwater harvesting.
(a) Suggest two methods of rain water harvesting.
(b) How can you store water without any water-borne diseases and germs multiplying in it?
(c) What values are seen in the members of society?
Ans. (a) Roof top and underground rain water harvesting.
(b) In close tanks and underground tanks.
(c) Members show responsible behaviour, socially just interaction and team work.