What are fossils? How are fossils formed and how is their age determined?
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1
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552
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April 4, 2019
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Explain the harmful effects of ozone depletion on Earth
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1
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564
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April 4, 2019
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(a) Why should ozone layer be protected to save the environment?
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1
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5310
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April 4, 2019
|
Give reason to justify the following: (a) The existence of decomposers is essential in a biosphere
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1
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5822
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April 4, 2019
|
“Energy flow in a food chain is unidirectional. Justify this statement
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1
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1087
|
April 4, 2019
|
“Our food grains such as wheat and rice, the vegetables and fruits
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1
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1028
|
April 4, 2019
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(a) What is an ecosystem? List its two main components
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1
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1088
|
April 4, 2019
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How is ozone formed in the higher level of atmosphere?
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1
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2839
|
April 4, 2019
|
What is “Green House Effect”? State two advantages and two disadvantage of this effect
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1
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621
|
April 4, 2019
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“Reuse is better than recycling of materials”. Give reason to justify this statement
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1
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1640
|
April 4, 2019
|
List two reasons to show that the existence of decomposers is essential in an ecosystem
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1
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2473
|
April 4, 2019
|
Why is Government of India imposing a ban on the use of polythene bags?
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1
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937
|
April 4, 2019
|
List the products of combustion of fossil fuels ? What are their adverse effects on the environment?
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1
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781
|
April 4, 2019
|
An environmentalist on visit to your school suggested the use of three R’s to save the environment
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1
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2467
|
April 4, 2019
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How are the following caused and what is the effect of each of them on our environment? (i) Depletion of ozone layer (ii) Acid rain
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1
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666
|
April 4, 2019
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List any four practices which help in protecting our environment
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1
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1184
|
April 4, 2019
|
Why is conservation of wildlife considered important for us? Give any two reasons
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1
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987
|
April 4, 2019
|
What is acid rain? Mention its two harmful effects
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1
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1287
|
April 4, 2019
|
Distinguish between biodegradable and non-biodegradable wastes. Give one example of each
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1
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582
|
April 4, 2019
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How does depletion of soil takes place? Suggest two ways to prevent it
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1
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600
|
April 4, 2019
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Describe how green house effect may cause atmospheric heating?
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1
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540
|
April 4, 2019
|
Waste of which of the following two materials in more polluting? Polythene or paper. Give reasons for your answer
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1
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1433
|
April 4, 2019
|
Write one negative effect, on the environment of affluent lifestyle of few persons of a society?
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1
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968
|
April 4, 2019
|
The depletion of ozone layer is a cause of concern why?
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1
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1931
|
April 4, 2019
|
Why should biodegradable and non-biodegradable wastes be discarded in two separate dust bins?
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1
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1118
|
April 4, 2019
|