I Answer the following questions briefly:
- What is Environment?
Answer: Environment is the surrounding where an organism, a community or an object exists.
2. Define ecology.
Answer: Ecology is the study of the interaction of living organisms with their physical, chemical and biological environment.
3. Name the different types of environmental pollution.
Answer: The different types of environmental pollution are,
1. Air Pollution
2. Water Pollution
3. Soil Pollution
4. Noise Pollution
4. What are the measures to control water pollution?
Answer: The measures to control water pollution are,
- Industrial effluents must be treated
- drinking water sources must be kept clean
- Sewage treatment plants, disposal of waste on the water bodies must be controlled, etc.
5. What is Bio-diversity?
Answer: The variety of flora (plants) and fauna (animals) in a region is known as biodiversity.
6. What is the environmental pollution?
Answer: Environmental pollution is the unfavourable alteration of our surrounding, wholly or partly by human action through direct and indirect effects.
7. What are the important air pollutions?
Answer; The important air pollutions are Volcanoes, forest fire, cosmic dust, Gases from industries, domestic use, automobiles, mining, nuclear power plants, nuclear explosions, etc.
8. What are the measures to control air pollution?
Answer: Measures to control air pollution areControl of gaseous pollutants, control of emission from automobiles, planting of more trees, use of non-conventional energy sources, awareness programme, legal control, literacy and education etc.
9. What is water pollution?
Answer: Water pollution is ‘alteration in physical, chemical and biological characteristics of water which may have harmful effects on human and aquatic life’.
10. Write the important sources of water pollution.
Answer: The important sources of water pollution are soil erosion, landslides, volcanic eruption, decay and decomposition of plants and animals, Industrial effluents, urban waste, domestic waste, agricultural waste, thermal waste, oil spill, offshore drilling, nuclear waste etc.
11. What are the important effects of water pollution?
Answer: The important effects of water pollution are, It spreads water-borne diseases and epidemics like cholera, typhoid, diarrhea, jaundice, TB, etc, causes death of aquatic life, affects irrigation water and on agricultural crops, nature and features of water etc.
12. What is Soil Pollution?
Answer: Soil pollution is ‘decrease in the quality of soils either due to human sources or natural sources or by both’.
13. What is noise Pollution?
Answer: Noise pollution is ‘any undesirable sound dumped into the atmosphere leading to health hazards’.
14. What are the important sources of noise pollution?
Answer; The important sources of noise pollution are Thunder, cyclones, heavy rainfall, hailstorms, waterfalls, ocean waves , Industrial noise, automobiles, air crafts, domestic noise, mining etc.
15. What are the effects of noise pollution?
Answer: Effects of noise pollution are, noise pollution causes temporary or permanent hearing problem, headaches, restlessness, cardiovascular diseases, Psychological disorder, behavioural changes, lack of concentration, etc.
16. What are the measures to control noise pollution?
Answer; Measures to control noise pollution are,
- Industries must be located away from the residential areas;
- construction of sound proof walls in the factories,
- restricting unnecessary use of sirens, horns and loud speakers;
- airports must be located away from the residential zones;
- Protective instruments the workers in the industries,
- Noise producing vehicles must be checked etc.
II Define the following:
- Biosphere
Answer: Earth is the only planet which has various forms of life on it. Biosphere is the part of the earth where life exists. The biosphere is the fourth component of the earth and it is the totality of all living things on earth.
2. Ecological balance
Answer: Ecology is the study of the interaction of living organisms with their physical, chemical and biological environment. In a natural environment, there is a perfect balance between the various organisms living together in the biosphere. This is known as ecological balance.
3. Global warming
Answer: The temperature of the earth is increasing slowly over the years. For the last few years global temperature has increased. This phenomenon is termed as Global warming.
4. Greenhouse effect
Answer: The use of fossil fuels is increasing greenhouse gases in the atmosphere. Carbon dioxide and other greenhouse gases trap the heat radiated from the earth. Thus increasing of greenhouse gases is causing an increase of temperature. This is called ‘Greenhouse effect’.
5. Ozone depletion
Answer: Ozone absorbs ultraviolet rays and protects all forms of life on the earth’s surface. In recent years the use of air conditioners, refrigerators, sprays and deodorants are destroying the ozone due to the synthetic chemicals released into the atmosphere, primarily ‘chlorofluorocarbons’ (CFC). This is called Ozone depletion.
6. Acid rain
Answer: Acid rain contains high amounts of acids particularly sulphuric acid and carbon monoxide. It is caused when the rain drops pass through the polluted atmosphere. The rainfall with poisonous acids kills marine organisms.
IV Activity:
- Collect information on the impact of global warming and enlist the ways of controlling global warming.
Answer: Effects scientists predicted, such as the loss of sea ice, melting glaciers and ice sheets, sea level rise, and more intense heat waves. Scientists predict global temperature increases from human-made greenhouse gases will continue. Severe weather damage will also increase and intensify.
Ways of controlling global warming.
Save energy at home. Much of our electricity and heat are powered by coal, oil and gas. Change your home’s source of energy. Eat more vegetables. Throw away less food. Walk, bike or take public transport. Switch to an electric vehicle. Consider your travel. Reduce, reuse, repair and recycle.
