Effects of Pollution - Questions & Answers
I. Choose the correct option:1. What is the effect of 150 dB of noise?
(a) Pain in ear
(b) Significant change in pulse rate
(c) Permanent damage to hearing
(d) Nausea, vomiting, dizziness
Answer: (b) Significant change in pulse rate
2. Birds avoid migrating to places where noise level is above 100 dB.
(a) 100 dB
(b) 90 dB
(c) 150 dB
(d) 140 dB
3. The process of depletion of oxygen from water bodies occurring either naturally or due to human activities.
(a) Biomagnification
(b) Eutrophication
(c) Bioaccumulation
(d) Pollution
Answer: (b) Eutrophication
4. The increase in the concentration of various toxic substances along the food chain:
(a) Biomagnification
(b) Eutrophication
(c) Bioaccumulation
(d) Pollution
Answer: (a) Biomagnification
5. The phenomenon of concentrated toxic deposition at the higher trophic level is known as:
(a) Biomagnification
(b) Eutrophication
(c) Bioaccumulation
(d) Pollution
Answer: (c) Bioaccumulation
6. Name the disease which resulted in numbness of body parts, vision and hearing problems and abnormal mental behaviour in Japan.
(a) Corona Virus
(b) Minamata
(c) Encephalitis
(d) Fluorosis
Answer: (b) Minamata
7. In Japan, pollution by heavy metal, cadmium, caused the disease called Itai-itai.
(a) Itai-itai
(b) Minamata
(c) Encephalitis
(d) Fluorosis
8. Which disease causes discolouring of dental enamel and black and brown stains on the teeth?
(a) Itai-itai
(b) Minamata
(c) Encephalitis
(d) Fluorosis
Answer: (d) Fluorosis
9. The Municipal Corporation of your city has banned all construction activities from 5 pm to 9 am. Why?
(a) To enable people to sleep.
(b) To reduce the noise produced by the activity.
(c) To reduce the physiological effects of noise pollution.
(d) All of the above.
Answer: (d) All of the above.
10. Assertion (A): Birds avoid migrating to places where noise level is above 100 dB.
Reason (R): Doctors and scientists have now medically confirmed that noise disturbs living organisms.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R does not explain A.
(c) A is true but R is false.
(d) A is false but R is true.
Answer: (a) Both A and R are true and R is the correct explanation of A.
Given below are scenes, list the pollutants generated by each. How does each pollutant affect (i) environment; (ii) humans and other living beings; and (iii) materials?
[Image a: Industrial smokestacks emitting thick smoke]
[Image b: A water body showing signs of pollution/eutrophication]
[Image c: The Taj Mahal surrounded by solid waste/garbage]
[Image d: Cooling towers of a nuclear power plant]
Answer:
Scene (a) - Air Pollutants: Pollutants include Carbon Monoxide, Sulphur Dioxide, Nitrogen Oxides, and Particulate Matter.
(i) Environment: Causes global warming and acid rain.
(ii) Humans/Living Beings: Causes respiratory infections, asthma, and lung damage. Destroys plant chlorophyll.
(iii) Materials: Soot damages painted surfaces, and acid gases corrode metals and disintegrate leather/paper.
Scene (b) - Water Pollutants: Pollutants include Nitrogenous fertilisers, Phosphates, and domestic/industrial effluents.
(i) Environment: Leads to eutrophication, depleting oxygen in the water.
(ii) Humans/Living Beings: Causes death of aquatic organisms. Biomagnification harms higher trophic levels. Causes water-borne diseases in humans.
(iii) Materials: Corrodes pipes and underwater structural foundations due to acidic water conditions.
Scene (c) - Solid Waste & Air Pollutants: Pollutants include decomposing solid waste, plastic, and Sulphur Dioxide in the air.
(i) Environment: Causes soil pollution, loss of fertility, and groundwater contamination.
(ii) Humans/Living Beings: Breeds pathogenic bacteria transmitting diseases like cholera and dysentery.
(iii) Materials: Sulphuric acid mist (acid rain) reacts with marble, causing discolouration and corrosion (like the Taj Mahal).
Scene (d) - Radioactive Pollutants: Pollutants include Uranium, Thorium, Plutonium, and radioactive wastes.
(i) Environment: High-level nuclear waste remains in the environment for hundreds of years, causing long-term ecological damage.
(ii) Humans/Living Beings: Causes severe genetic variations in offspring, cancer (thyroid, breast, lung), and mass animal casualties.
(iii) Materials: High radiation can cause degradation of certain industrial and structural materials over time.
1. How does noise pollution affect animals?
Answer: Noise pollution negatively affects biological performance. Birds avoid migrating to places where noise levels exceed 100 dB, and some birds completely stop laying eggs. High noise emissions can also cause miscarriages in mammals and fishes.
2. What major harm is done to human beings by air pollution?
Answer: Air pollution causes short-term effects like irritation in the eyes, nose, and throat, along with headaches and nausea. Long-term exposure leads to chronic respiratory diseases, lung cancer, cardiovascular diseases, and severe damage to nerves, brain, liver, and kidneys.
3. How are animals affected by air pollution?
Answer: Animals feeding on grass coated with polluted particulate matter suffer from toxic poisoning, such as arsenic poisoning. Lead poisoning in pets can result in bronchitis and loss of appetite.
4. What is the effect of oil spills on marine life?
Answer: Sea water polluted with crude oil leakage coats the surface of the water, preventing oxygen transfer and sunlight penetration, which suffocates marine organisms and directly leads to their death.
5. What causes water-borne diseases? Name two water-borne diseases.
Answer: Water-borne diseases are caused by pathogens (disease-causing bacteria, viruses, and protozoa) present in contaminated drinking water and sewage. Two examples are cholera and typhoid.
6. In what way does soil pollution affect human beings?
Answer: Soil containing pathogenic bacteria and intestinal worms transmits diseases to humans when they consume contaminated fruits and vegetables. Additionally, radioactive fallout absorbed by vegetation enters the human food chain through grazing animals, causing serious abnormalities.
7. A landfill was reclaimed and sturdy plants were grown on it instead of crops or fruit trees. Why?
Answer: Landfills contain highly polluted soil infused with industrial waste, pathogens, and toxic heavy metals. If edible crops or fruit trees were grown, these toxins and disease-causing pathogens would be absorbed by the plants and transmitted directly into the human food chain. Sturdy, non-edible plants prevent this transfer while helping to reclaim the soil.
8. Give the impact of radiations on human body.
Answer: Radiations cause genetic variations, which are harmful changes transmitted to future offspring. Short-term somatic variations include organ damage, resulting in breast, thyroid, lung, and brain cancers, as well as sterility and defective eyesight.
9. Why are nuclear radiations more dangerous than other forms of pollution?
Answer: Nuclear radiations are exceptionally dangerous because high-level radioactive products remain in the environment for several hundred years. The toxic effects penetrate deep into the food chain and cause permanent genetic mutations that plague generations.
10. Crude oil from a refinery has leaked into the Kosasthalaiyar river (north of Chennai), the biodiverse Ennore creek (where many migratory birds come) and the Bay of Bengal. This has caused pollution. List what all could have been impacted and how?
Answer: The oil spill would heavily impact marine organisms, aquatic plants, and migratory birds. The oil forms a toxic layer on the water, depleting oxygen and suffocating fish and aquatic plants. For migratory birds, oil coats their feathers, destroying their natural insulation and buoyancy, often leading to death by drowning or hypothermia. Toxic compounds would also bioaccumulate in surviving species, permanently poisoning the local food web.
1. (a) State briefly how is noise pollution detrimental to human health.
Answer: Continuous exposure to noise above 100 dB causes permanent deafness and interferes with sleep and communication. It triggers psychological distress, neurosis, mental illness, cardiovascular diseases, and stomach ulcers.
(b) How does air pollution affect the environment?
Answer: The increase in greenhouse gases causes Global Warming. This leads to melting of glaciers and snowlines, abnormal rise in winter and night temperatures, excessive evaporation leading to droughts, and rising sea levels that cause coastal flooding and salt intrusion.
(c) Explain how the accumulation of nutrients and chemicals in the water prove fatal for the marine organisms.
Answer: Nutrients from fertilisers and sewage cause a process called eutrophication, creating a massive overgrowth of algae. This algal bloom blocks sunlight and rapidly depletes the dissolved oxygen in the water. Without oxygen, most marine organisms suffocate and die.
(d) With the help of a well labelled diagram explain how the accumulation of toxic substances increases as we move up the food chain.
Answer: (Diagram description as per the text) This process is called Biomagnification. Toxic substances (like DDT) that do not degrade enter the water at low concentrations (e.g., 0.04 ppm in Producers/algae). Primary consumers (small fishes) eat the algae, increasing the toxin concentration (0.23 ppm). Secondary consumers (larger fishes) eat the small fishes, further concentrating the toxins (2.07 ppm). Finally, tertiary consumers (birds) eat the large fishes, receiving a lethal accumulated dose of the toxin (13.8 ppm).
2. (a) State any two effects each of soil pollution on human beings and environment.
Answer: Human Beings: 1. Consumption of contaminated crops transmits pathogenic bacteria and viruses. 2. Toxic heavy metals and pesticides travel up the food chain causing serious illnesses. Environment: 1. Nitrogenous fertilisers produce toxic nitrate concentrations in plant leaves. 2. Chemical wastes seep deep underground, polluting critical groundwater resources.
(b) Name three common air pollutants and their effects on human health.
Answer: 1. Carbon Monoxide: Damages lungs and severely reduces the oxygen-carrying capacity of the blood. 2. Sulphur Dioxide: Obstructs breathing and causes irritation of the eyes and throat. 3. Lead: Causes serious brain damage, affects physical growth, and leads to high blood pressure.
(c) What are pathogens? How do they enter human body? Name any three diseases caused by these pathogens.
Answer: Pathogens are disease-causing microorganisms like bacteria, viruses, and protozoa. They enter the human body through the consumption of contaminated drinking water or infected food. Three diseases caused by them are cholera, typhoid, and jaundice.
(d) State with examples the effects of radiations on the human beings and environment.
Answer: Human Beings: Exposure causes acute radiation sickness, cancers, and genetic mutations. Example: During the 1986 Chernobyl disaster, 237 people suffered acute radiation sickness, resulting in 31 direct deaths. Environment: Radiation destroys vegetation and sterilises the ecosystem. Example: At Chernobyl, four square kilometres of pine forest turned reddish-brown and died (the "Red Forest"), and animals entirely stopped reproducing.
3. Read the passage given below...
(a) How do the gases released by the power plants affect human health and well-being?
Answer: Gases like NOX and SO2 form fine particles and ground-level ozone. Breathing these pollutants leads to severe adverse health effects, including new asthma cases, asthma exacerbations, heart attacks, premature deaths, and lost school and work days.
(b) How does the pollution from the power plants affect the environment?
Answer: NOX and SO2 emissions cause acid rain, damaging terrestrial and aquatic ecosystems. Furthermore, large-scale emissions of carbon dioxide significantly contribute to global warming and climate change, directly threatening biological communities.
(c) What is climate change? How do power plants contribute to it?
Answer: Climate change refers to long-term shifts in global temperatures and weather patterns. Fossil fuel-fired power plants are the second largest emitters of Carbon Dioxide (a major greenhouse gas). These emissions trap heat in the earth's atmosphere, driving up global temperatures and altering the climate.
(d) What can be done to reduce the harm caused by use of power plants?
Answer: We can reduce harm by transitioning from fossil fuels to renewable energy sources (like solar and wind), installing advanced scrubber technologies in smokestacks to capture NOX and SO2 before they are released, and improving energy efficiency to lower overall electricity demand.
1. The apparent lack of concern for the effects of pollution seems to be the reason for not implementing plans to prevent pollution. Justify this statement with examples.
Answer: Despite clear evidence of pollution's devastating impacts, short-term economic interests often outweigh environmental protection. For example, industries continue to dump untreated chemical waste into rivers to save money, leading to tragedies like the Minamata disease. Similarly, fossil fuel power plants are still heavily relied upon for cheap energy, even though we know their greenhouse gas emissions are actively driving deadly climate change.
2. Which is the most visible affect of pollution on human beings in your city? What are the causes and possible remedies?
Answer: In Indian cities, the most visible effect is the rise in respiratory problems like asthma and chronic coughing, coupled with eye irritation. Causes: High levels of vehicular exhaust, unchecked construction dust, and industrial emissions. Remedies: Strictly implementing emission tests for vehicles, shifting to clean public transport (like electric buses), heavily regulating industrial smoke, and planting dense urban green covers.
3. Northern India is enveloped in smog in the month of November. List the causes for the same.
Answer: The smog in Northern India during November is primarily caused by: 1. Agricultural stubble burning by farmers in neighbouring states clearing their fields. 2. Heavy vehicular and industrial emissions. 3. Smoke from firecrackers burst during festivals. 4. Winter temperature inversions, which cause a layer of cold air to trap the pollutants close to the ground, preventing them from dispersing.