Important Short Questions and Answers: Environmental Pollution

Environmental Pollution

1. Define Environmental Pollution.

Environmental Pollution is defined as any undesirable change in the physical, chemical, or biological characteristics of any component of the environment (air,water,soil)which can cause harmful effects on various forms of property.

2. Suggest four important sources of air pollution.

The sources of air pollution are volcanic eruptions, fest fires, biological decay, thermal power plants, vehicular emissions etc.,

3. What is meant by BOD and COD? 

BOD: BOD is the amount of oxygen required for the biological decomposition of organic matter present in the water.

COD: COD is the amount of oxygen required f chemical oxidation of organic matter using oxidizing agent.

4. Name the sources and effects of marine pollution. Sources: Dumping the waste, oil pollution and shipment.

Effects: The continuous oil films inhibit photosynthesis and absorption of oxygen. This inhibits the growth of plankton. All aquatic animals depend either directly indirectly on plankton, which is the basis of the tropic chain.

5. Mention the sources of soil pollution.

Domestic wastes include garbage, rubbish material like glass, plastics, metallic cans, paper, fibers, cloth rags, containers, paints, varnishes etc.

6. Define green house effect.

The greenhouse effect is a naturally occurring process that makes the earth warmer by trapping more energy in the atmosphere. The green house gases absorb and hold heat from the sun, preventing it from escaping back into the space; much like a green house absorbs and holds the sun’s heat Industrial wastes are the effluents discharged from chemical industries, paper and pulp mills, tanneries, textile mills, steel industries, distilleries, refineries, pesticides and fertilizer industries, pharmaceutical industries, food processing industries, cement industries, thermal and nuclear power plants, mining industries etc.

7. List the ozone depleting chemicals.

Chlorofluorocarbons (CFC) are responsible for ozone layer depletion.

8. Define the term Noise Pollution.

Noise pollution is the disturbing or excessive noise that may harm the activity or balance of human or animal life. The source of most outdoor noise worldwide is mainly caused by machines and transportation systems, motor vehicles, aircraft, and trains.

9. Define biological oxygen demand and chemical oxygen demand. Write its environmental impacts.

Biological Oxygen Demand (BOD) is defined as the amount of DO required to aerobically decompose biodegradable organic matter over a period of 5 days at 20○C.

Chemical oxygen demand (COD) is commonly used to indirectly measure the amount of organic compounds in water.

Increase in BOD and COD values degrades the quality of water. It is harmful to aquatic organisms and causes toxic effects at various levels of food chain.

10.            What are the effects of Global warning?

a) More heat waves

b) Expansion of desert area

c) Natural fires in forestlands

d) More evaporation of water from oceans and water bodies

e) Melting of ice caps in Arctic and Antarctica regions

f) More cloud formation in the atmosphere.

g) Shorter and warmer winters and longer and shorter summer.

h) Changes in pattern of rainfall i) Rise in sea level

j) Flooding and submergence of low lying coastal areas

11.Give two effects of noise pollution on human beings.

(i)            It causes contraction of blood vessels, makes the skin pale, leads to excessive secretion of adrenalin hormone in to blood stream which is responsible for high blood pressure.

(ii)          It causes muscles to contract leading to nervous breakdown, tension etc.,

12 Define thermal pollution. 

Thermal pollution is defined as the addition of excess of undesirable heat to water

that makes it harmful to man, animal aquatic life otherwise causes significant departures from the normal activities of aquatic communities in water.

13. Mention the effects of solid waste.

*Spreading of fungal diseases; *Bad odours; *Burning of waste produce chemicals which are harmful to human life; *Contaminates water & *Affects the characteristics of soil .

14. What are the damages caused by the nuclear radiations?

Genetic damages – The damage is caused by radiations, which induce mutations in DNA. The damage is often seen in the offsprings and may be transmitted upto several generations.

Somatic damage – This includes burns, miscarriages, eye cataract, bone cancer etc.

15.            Mention the activities involved in solid waste management.

·        Waste generation,

·        onsite handling ,storage and processing

·        collection

·        transfer and transport

·        processing and recovery and disposal

15.            Mention the activities involved in solid waste management.

·        Waste generation,

·        onsite handling ,storage and processing

·        collection

·        transfer and transport

·        processing and recovery and disposal