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100 questions in this collection · Page 4 of 10
Question 31 of 100
📘 CLASS XII
Environmental Issues
Consider the following statements about the Chipko Movement and Joint Forest Management (JFM):
I. The Chipko Movement was initiated in 1974 in the Garhwal Himalayas. II. In the Chipko Movement, local women showed enormous bravery in protecting trees from contractors by hugging them. III. The Joint Forest Management (JFM) concept was introduced by the Government of India in the 1950s. IV. Under JFM, local communities manage forests and in return get forest products like fruits, gum, rubber, and medicine.
Which of the statements given above are correct?
The Chipko Movement began in 1974 in the Garhwal Himalayas, with local women protecting trees by hugging them. JFM was introduced by the Government of India during the 1980s, not the 1950s. Local communities receive forest products in return for protecting forests.
Question 32 of 100
📘 CLASS XII
Environmental Issues
Read the following statements regarding the effects of Ultraviolet (UV) radiation:
I. UV radiation of wavelengths longer than UV-B is completely absorbed by the Earth's atmosphere. II. UV-B damages DNA, and mutations may occur. III. It causes aging of skin, damage to skin cells, and various types of skin cancers. IV. A high dose of UV-B causes inflammation of the cornea, known as snow-blindness.
Which of the statements given above are correct?
UV radiation with wavelengths shorter than UV-B is almost completely absorbed by the atmosphere. UV-B reaches the Earth's surface and can damage DNA, cause skin cancer, and lead to inflammation of the cornea (snow-blindness).
Question 33 of 100
📘 CLASS XII
Environmental Issues
With reference to the Montreal Protocol, consider the following statements:
I. It is an international treaty signed at Montreal, Canada, in 1987. II. It became effective in 1989. III. Its primary objective is to control the emission of ozone-depleting substances. IV. It laid down separate, definite roadmaps for developed and developing countries to reduce CFC emissions.
Which of the statements given above are correct?
All four statements are correct. The Montreal Protocol was signed in 1987, came into force in 1989, aims to control ozone-depleting substances, and provides separate implementation schedules for developed and developing countries.
Question 34 of 100
📘 CLASS XII
Environmental Issues
Read the following statements regarding soil degradation processes:
I. Fertile topsoil takes centuries to develop, but can be easily removed by over-cultivation, unrestricted grazing, and deforestation. II. Desertification is a major problem nowadays, particularly due to increased urbanisation. III. Irrigation without proper drainage leads to waterlogging in the soil. IV. Waterlogging draws salt to the surface, which is deposited as a thin crust or collects at root zones.
Which of the statements given above are correct?
All the statements are correct. Fertile topsoil develops over centuries but is easily lost due to over-cultivation, unrestricted grazing and deforestation. Desertification is a major problem, while poor drainage causes waterlogging and brings salts to the soil surface, resulting in salinity.
Question 35 of 100
📘 CLASS XII
Environmental Issues
Consider the following statements about CPCB regulations and particulate air pollutants:
I. The Central Pollution Control Board (CPCB) states that particulate size 2.5 micrometers or less in diameter (PM 2.5) causes the greatest harm to human health. II. These fine particles can be inhaled deep into the lungs, causing breathing and respiratory symptoms. III. Particulate matter of PM 2.5 size is easily filtered out by standard electrostatic precipitators. IV. They cause inflammation and damage to the lungs, and can lead to premature deaths.
Which of the statements given above are correct?
PM2.5 particles are the most harmful because they penetrate deep into the lungs, causing inflammation, respiratory diseases and premature deaths. These extremely fine particles are generally not removed by ordinary electrostatic precipitators, making Statement III incorrect.
Question 36 of 100
📘 CLASS XII
Environmental Issues
With reference to the legislative acts passed by the Government of India, match the years in the following statements:
I. The Water (Prevention and Control of Pollution) Act was passed in 1974. II. The Air (Prevention and Control of Pollution) Act came into force in 1981. III. The Environment (Protection) Act was passed in 1986. IV. The Air Act was amended to include noise as an air pollutant in 1989.
Which of the statements given above are correct?
The Water Act (1974), Air Act (1981) and Environment Protection Act (1986) are correctly matched. The Air Act was amended to include noise as an air pollutant in 1987, not 1989.
Question 37 of 100
📘 CLASS XII
Environmental Issues
Read the following statements about Delhi's fuel specifications and emission steps:
I. Euro III norms stipulate that sulfur be controlled at 350 ppm in diesel and 150 ppm in petrol. II. Under Euro III, aromatic hydrocarbons are to be contained at 42 percent of the concerned fuel. III. The roadmap target is to reduce sulfur to 50 ppm in both petrol and diesel and bring down aromatic content to 35 percent. IV. Currently, Bharat Stage II mass emission norms are still applicable in major metro cities of India.
Which of the statements given above are correct?
Euro III norms specify sulfur limits of 350 ppm in diesel and 150 ppm in petrol with aromatic hydrocarbons limited to 42%. The long-term target is 50 ppm sulfur and 35% aromatics. Bharat Stage II norms are no longer applicable, making Statement IV incorrect.
Question 38 of 100
📘 CLASS XII
Environmental Issues
Regarding the composition of domestic wastewater, read the following statements:
I. A mere 1 percent impurity makes domestic sewage completely unfit for human use. II. Dissolved salts such as nitrates and phosphates are the easiest to remove from sewage water. III. Domestic sewage primarily contains biodegradable organic matter, which is decomposed by bacteria and fungi. IV. Solids are relatively easy to remove compared to toxic metal ions and organic compounds.
Which of the statements given above are correct?
A mere 0.1% impurity makes domestic sewage unfit for human use. Dissolved nutrients such as nitrates and phosphates are the most difficult to remove. Domestic sewage mainly contains biodegradable organic matter, while suspended solids are comparatively easier to remove.
Question 39 of 100
📘 CLASS XII
Environmental Issues
Consider the following statements regarding the concentration of DDT at different trophic levels in an aquatic food chain:
I. The concentration of DDT starts in water at 0.003 ppb. II. In zooplankton, the concentration of DDT reaches 0.04 ppm. III. In small fish and large fish, the DDT concentrations are 0.5 ppm and 2 ppm respectively. IV. Due to biomagnification, the concentration in fish-eating birds reaches a maximum of 25 ppb.
Which of the statements given above are correct?
Biomagnification increases DDT concentration from 0.003 ppb in water to 0.04 ppm in zooplankton, 0.5 ppm in small fish, 2 ppm in large fish and 25 ppm in fish-eating birds. Statement IV is incorrect because it mentions ppb instead of ppm.
Question 40 of 100
📘 CLASS XII
Environmental Issues
Analyze the following statements about Eutrophication of lakes:
I. Young lakes have warm, nutrient-rich water that supports extensive aquatic life. II. Over centuries, as silt and organic debris pile up, the lake grows shallower and warmer. III. Marsh plants take root in the shallows, converting the lake basin into land. IV. Cultural eutrophication is the accelerated aging of lakes due to human effluents from industries and homes.
Which of the statements given above are correct?
Young lakes are cold, clear and nutrient-poor with limited organic life. Over time they become shallower and warmer, marsh vegetation colonizes the shallows, and human activities accelerate this natural aging process through cultural eutrophication.