Q21. The main components responsible for the formation of acid rain are:
Environmental and Ecological Changes and Impact Assessment: RAS Prelims MCQs
168 RAS Prelims MCQs on environmental and ecological changes and impact assessment cover ecosystem concepts, pollution, climate and environmental law. Ecotones, decomposers, primary productivity, secondary pollutants, the greenhouse effect, the EIA Notification 2006, the Environment (Protection) Act 1986 and the Aravalli mining ban are asked as definitions, laws and statements.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 21–30 of 168 questions
Q22. Particulate Matter (PM) 2.5 is particularly dangerous to human health because:
Explanation
Extremely small airborne particles pose a significant threat to human health due to their ability to bypass the natural filtration systems in the nose and throat. These fine particles can travel deep into the lungs and even pass directly into the bloodstream. Once inside the circulatory system, they can cause widespread inflammation and contribute to various respiratory and cardiovascular diseases over time.
Q23. Photochemical smog is characterized by the presence of which secondary pollutant?
Explanation
Photochemical smog is a complex mixture of pollutants formed when nitrogen oxides and volatile organic compounds react in the presence of sunlight. This type of haze contains several harmful secondary substances. One particularly toxic compound is known for causing eye irritation and damaging plant tissues. Its presence is a key indicator of the chemical reactions taking place in polluted urban air.
Q24. Regarding indoor air pollution, consider the following statements:
I. Radon gas is a natural source of indoor air pollution.
II. Biomass burning in rural kitchens is a major cause in developing countries.
III. Indoor air pollution cannot cause chronic obstructive pulmonary disease (COPD).
Which of the above statement(s) is/are correct?
I. Radon gas is a natural source of indoor air pollution.
II. Biomass burning in rural kitchens is a major cause in developing countries.
III. Indoor air pollution cannot cause chronic obstructive pulmonary disease (COPD).
Which of the above statement(s) is/are correct?
Explanation
Air quality inside buildings can be worse than outside due to various factors. Natural sources like radioactive gases seeping from the ground and the use of solid fuels for cooking in poorly ventilated spaces are major concerns. Long-term exposure to these pollutants is a well-documented cause of serious respiratory conditions, including chronic lung diseases that significantly impact the health of vulnerable populations.
Q25. The National Air Quality Index (AQI) in India considers how many pollutants for measurement?
Explanation
To provide a clear and easily understandable measure of air quality, authorities monitor a specific group of major pollutants.
Q26. Which of the following is an occupational respiratory disease common among coal miners?
Explanation
Workers in certain industries face specific health risks due to the substances they inhale daily. Those employed in underground mining are often exposed to high levels of fine carbon dust. Over many years, this dust accumulates in the lungs, leading to inflammation and scarring. This chronic respiratory condition reduces lung function and is a well-known hazard associated with the extraction of coal.
Q27. Fly ash is a major environmental pollutant generated primarily by:
Explanation
A fine, powdery byproduct is produced when pulverized coal is burned to generate electricity. This material is carried away from the combustion chamber by exhaust gases. While it can be captured by filtration systems, its disposal remains a significant environmental challenge. If not managed properly, it can contaminate air, soil, and water near the large facilities that rely on solid fuels.
Q28. The ‘Air (Prevention and Control of Pollution) Act’ was enacted in India in which year?
Explanation
To address the growing problem of atmospheric contamination, the Indian government established a dedicated legal framework in the early nineteen-eighties. This legislation provides for the prevention, control, and abatement of air pollution. It also empowered specific boards to set standards and regulate emissions from various industrial and domestic sources, marking a significant step in the country’s efforts toward environmental protection and management.
Q29. Which of the following technologies is used in smokestacks to reduce particulate matter emissions?
Explanation
Large industrial facilities use specialized equipment to remove fine particles from exhaust gases before they are released into the atmosphere. One highly effective device uses high-voltage electricity to give the particles a charge, causing them to stick to collection plates. This method allows for the removal of a vast majority of the dust and soot, significantly improving the local air quality.
Q30. Given below are two statements, one is labelled as Assertion (A) and the other as Reason (R):
Assertion (A): Excessive discharge of nutrients into lakes leads to a decrease in dissolved oxygen.
Reason (R): Nutrient enrichment promotes rapid algal blooms, which consume oxygen upon death and decomposition.
Assertion (A): Excessive discharge of nutrients into lakes leads to a decrease in dissolved oxygen.
Reason (R): Nutrient enrichment promotes rapid algal blooms, which consume oxygen upon death and decomposition.
Explanation
When water bodies receive an excess of nutrients, it triggers a rapid increase in the population of microscopic aquatic plants. While these organisms produce oxygen during the day, their eventual death leads to a massive decomposition process by bacteria. This biological breakdown consumes vast amounts of the oxygen dissolved in the water, creating a hostile environment for fish and other aquatic life.Answer key for these questions
| Q | Correct answer |
|---|---|
| 21 | (a) Sulfur dioxide and Nitrogen oxides |
| 22 | (d) It enters the blood via natural defenses |
| 23 | (b) Peroxyacetyl nitrate (PAN) |
| 24 | (a) I and II only |
| 25 | (b) Eight |
| 26 | (a) Pneumoconiosis (Black lung disease) |
| 27 | (b) Thermal power plants using coal |
| 28 | (b) 1981 |
| 29 | (a) Electrostatic precipitators |
| 30 | (a) Both A and R are true and R is the correct explanation of A. |
Key facts from Environmental and Ecological Changes and Impact Assessment
- An ecosystem is made of interacting organisms and their physical environment; an ecotone is a zone of transition between ecosystems.
- Saprotrophs convert complex organic matter into simple substances; gross primary productivity is the rate at which producers create organic matter.
- Plants release water vapour through transpiration.
- Ground-level ozone is a secondary pollutant; CO, SO₂ and PM10 are primary pollutants.
- The greenhouse effect is the trapping of heat by atmospheric gases.
- Category B2 projects are exempt from public consultation under the EIA Notification 2006; the Supreme Court banned mining in the Aravalli range in Haryana and Rajasthan.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Environmental and Ecological Changes and Impact Assessment?
This page has 168 practice MCQs on Environmental and Ecological Changes and Impact Assessment (Health, Environment and Agriculture). Each has the correct answer, and most have an explanation.
What is a secondary pollutant?
A pollutant that is not emitted directly but forms in the air from primary pollutants. Ground-level ozone is the standard example, formed when nitrogen oxides and volatile organic compounds react in sunlight.
What is an ecotone?
A zone of transition between two different ecosystems, such as the area between a forest and a grassland. It often has more species than either neighbour because it has species of both.
Which projects are exempt from public consultation under EIA 2006?
Category B2 projects, which have less environmental impact. Category A and B1 projects need public consultation as part of the clearance process, which is the main way local people are heard.