NCERT - Environmental Issues Questions and Answers of Class 12 Biology | GkSeries

Questions
61 World Environment Day is celebrated every year on ______.
1 5th March
2 15th April
3 15th May
4 5th June

Answer: 5th June
62 SO2 pollution is indicated by
1 Deschampsia (grasses)
2 Sphagnum (Mosses)
3 Usnea (Lichens)
4 Cucurbita (climbers)

Answer: Usnea (Lichens)
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63 Fluoride pollution mainly affects
1 Brain
2 Teeth
3 Heart
4 Kidney

Answer: Teeth
64 As it travels along the food chain, the concentration of DDT
1 Increases
2 Remains constant
3 Decreases
4 Fluctuates randomly

Answer: Increases
65 SO2 and NO2 produce pollution by increasing
1 Neutrality
2 Acidity
3 Alkalinity
4 Buffer action

Answer: Acidity
66 Gas leaked during Bhopal tragedy was
1 Ethyl isothiocyanate
2 Sodium isothiocyanate
3 Potassium isothiocyanate
4 Methyl isocyanate

Answer: Methyl isocyanate
67 Addition of phosphates and nitrates/fertilizers into water leads to
1 Increased algal growth
2 Nutrient enrichment (eutrophication)
3 Reduced algal growth
4 Increased growth of decomposers

Answer: Nutrient enrichment (eutrophication)
68 Pollutants having most lasting effect are
1 Pesticides
2 Smoke from chimneys
3 SO2
4 CO

Answer: Pesticides
69 Compounds of ______ cause Minamata disease
1 mercury
2 cadmium
3 cobalt
4 fertilisers

Answer: mercury
70 Algal bloom results in
1 Global warming
2 Salination
3 Eutrophication
4 Biomagnification

Answer: Eutrophication
71 The range of normal human hearing is in the range of
1 10 Hz to 80 Hz
2 50 Hz to 80 Hz
3 50Hz to 15000 Hz
4 15000 Hz and above

Answer: 50Hz to 15000 Hz
72 Growing agricultural crops between rows of planted trees is known as
1 Social forestry
2 Jhum
3 Taungya system
4 Agroforestry

Answer: Jhum
73 Maximum threat to the world is from
1 Global warming
2 Ozone hole
3 Water pollution
4 Soil erosion

Answer: Ozone hole
74 Carbon released in the atmosphere increase the level of
1 Methane
2 GHGs
3 Gases
4 Air Pollution

Answer: GHGs
75 Which one of the following is a wrong statement?
1 Greenhouse effect is a natural phenomenon
2 Eutrophication is a natural phenomenon in freshwater bodies
3 Most of the forests have been lost in tropical areas
4 Ozone in upper part of atmosphere is harmful to animals

Answer: Ozone in upper part of atmosphere is harmful to animals

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