Pollution. I choose correct answer

Transcription

1 Pollution I choose correct answer 1. A reason for pollution which may not be always natural is mining 2. The common name for the unavoidable end product of human activity that spoils the quality of biosphere is DDT 3. One of the following is a biodegradable pollutant.. kitchen waste 4. One of the following is not a pollutant discharged from industries..sewage II Fill in the blanks 1. Human and animal waste ( faeces ) is an example of biodegradable pollutant. 2. The fuel which emits less pollutants is kerosene or LPG 3. Green house effect causes an increase in temperature. 4. Organic farming is suggested to avoid soil pollution. III Match the following A B 1. plastic non-biodegradable 2. kitchen waste biodegradable 3. sulphur dioxide air pollutant 4. pollen dust biological air pollutant 5. bio gas alternative fuel IV Answer the following 1. Define pollution and mention the three areas of pollution you have studied. A. Any undesirable change in the air, water, or soil which disturbs the delicate balance of the natural environment is called pollution. a) Air pollution

2 b) Soil pollution c) Water pollution 2. What are biodegradable pollutants? Give two examples. A. Any pollutant when converted into its harmless state through the activity of organisms ( chiefly bacteria ) is called a biodegradable pollutant. Example kitchen waste, domestic sewage. 3. Define non-biodegradable pollutants? Give two examples. A. Any pollutant which is not converted into its harmless state by organisms and remains unchanged for a long time is called a non-biodegradable pollutant. Example plastic, heavy metals 4. Differentiate biodegradable pollutants from non biodegradable pollutants. Give an example for each. Biodegradable pollutants example kitchen waste has undergoes decomposition by the activity of bacteria. Whereas non biodegradable pollutants eg Plastic cannot be converted into its harmless state by organisms and remain unchanged for a long time. 5. Make a list of any four causes of air pollution. A. Causes of air pollution a) Fuels used in industries, vehicles and thermal power plants emit carbon monoxide, sulphur dioxide, nitrogen dioxide and other gases as well as small particles. b) Chemical pesticides and insecticides sprayed on crops. c) Carbon dioxide and methane released into air during the decay of organic matter such as fallen leaves and found waste. d) Dust particles produced during construction activities such as roads, buildings and factories. e) Carbon dioxide, carbon monoxide and small particles released by burning wood, agricultural waste and dung cakes. 6. Menton any four causes of water pollution. A. Causes of water pollution a) Industrial wastes containing harmful chemicals b) Industrial discharge of hot water into water bodies.

3 c) Domestic wastes and sewage containing harmful microorganisms and detergents. d) Seepage of water containing fertilizers, pesticides and weedicides from agricultural fields and entry of agricultural wastes. e) Discharge of mining wastes. f) Oil spillage. 7. Explain how soil is polluted. A. When components harmful to human beings and other organism get into the soil, the natural quality of soil gets changed or soil gets polluted. 8. State the effects of air pollution. A. Effects of air pollution a) Affects health of human beings seriously. Affects the respiratory organs ( lungs ). It causes diseases such as asthma, bronchitis, carbon monoxide blood poisoning and even cancer. b) Harms agricultural crops and other plants and reduces their yield. c) Long term air pollution causes acid rain. 9. What are the effects of water pollution? A. Effects of water pollution a) Polluted water is unstable for drinking and other domestic activities, agricultural practices and even for aquatic organisms. b) Harmful micro organisms present in water may cause several diseases such as diarrhea, jaundice, typhoid and others. c) Hazardous chemicals may cause nervous disorders, affect vital organs such as liver and kidney to bring about permanent damage to the body. d) Harmful chemicals present in water even kill plants and animals. e) Pollution of water results in reduction of dissolved oxygen. This affects survival of aquatic organisms. 10. Mention any two effects of soil pollution. A. Effects of soil pollution a) Soil pollution affects useful organisms such as earthworms, ants and others. b) The polluted soil becomes unusable. 11. Suggest any five measures to reduce air pollution

4 A. Measures to reduce air pollution a) Decreasing emissions from industries and motor vehicles using clean technologies and regular maintenance of engines. b) Using fuel which emit less pollutants. For example kerosene, Liquid Petroleum Gas (LPG) or sulphur free petrol. c) Using public transport like buses and trains and minimizing the use of private vehicles like cars, motorcycles etc. Car pool may be good idea. d) Using renewable sources of energy such as solar energy, wind energy and bio gas. e) Avoiding bursting of crackers. f) Growing more trees which act as screens or insulators against dust and other particles and even absorb pollutants like oxides of sulphur. g) Strict enforcement of anti pollution laws. 12. What measures do you suggest to reduce water pollution? A. Water pollution can be reduced by a) Releasing only treated sewage into natural water bodies. b) Cooling the over-heated waste water from industries before letting into water bodies. c) Preventing the flow of water from agricultural fields into the natural water bodies. d) Strict enforcement of anti-water pollution laws. 13. Suggest any two control measures to reduce soil pollution. A. Soil pollution can be reduced by a) Separating the wastes into biodegradable, non-biodegradable and hazardous wastes, and disposing them using scientific method. b) Decreasing the over use of fertilizers and pesticides like neem cake. c) Disposing the industrial wastes properly. d) Growing and maintaining plants that absorb some of the pollutants. 14.Bring out the relationship between growing trees and reducing air pollution. A. Trees act as a insulators against dust and other particles and even absorb pollutants like oxides of sulphur. 15. How do harmful chemicals in the soil effect us?

5 Ans. Harmful chemicals in the soil get into the plants and their products such as fruits,seeds, vegetables and grains. When human beings consume these, their health is affected. 16. Why do you think stagnant water bodies like ponds and tanks appear green? Ans. If the stagnant water bodies like ponds and tanks appear will think that water is no more clean. 17. Why is sewage treatment is necessary.? Ans Sewage treatment is necessary because sewage containing harmful micro organisms and detergents. 18. Organic farming is preferred today why? Ans. Organic farming is preferred today because no chemical fertilizers and pesticides are used in this type of farming, the produce is less contaminated.