UPSC IAS Prelims 2021: Important Questions on Environment - Topic 2 (Pollution)
UPSC: UPSC Civil Service Prelims 2021 exam is scheduled for June 27. Considering the dynamic exam syllabus, preparing for the exam comes with different kinds of hurdles. Some aspirants struggle at memorizing the facts while others face difficulty in solving questions even from well-prepared topics. To help the aspirants’ shred exam fear and be fluent with the exam pattern, Jagran Josh has come up with this new “Important Questions and Answers for Prelims” series. Aspirants can solve these topic-wise important questions to test their preparation level.
Also Check: Important Topics from Environment & Ecology Syllabus
Ques 1: Consider the following statements.
- Microplastics are small pieces of plastic that occur in the environment as a consequence of plastic pollution.
- Microplastics are present in cosmetics, synthetic clothing, plastic bags, and bottles.
- Microplastics are biodegradable, unlike microplastics.
Which of the above statements is/are correct?
a) 1 only
b) 1 and 2 only
c) 2 and 3 only
d) All of the above
Ans: b
| Explanation: Microplastics, small pieces of plastic, less than 5 mm (0.2 inches) in length, that occur in the environment as a consequence of plastic pollution. Microplastics are present in a variety of products, from cosmetics to synthetic clothing to plastic bags and bottles. Many of these products readily enter the environment in wastes. Microplastics are not biodegradable. Thus, once in the environment, primary and secondary microplastics accumulate and persist. |
Ques 2: The increasing amount of carbon dioxide in the air is slowly raising the temperature of the atmosphere because it absorbs
a) the water vapor of the air and retains its heat
b) Infrared part of solar radiation
c) the ultraviolet part of the solar radiation
d) all the solar radiations
Ans: b
| Explanation: Greenhouse gases absorb long-wave infrared radiations from the earth and emit it again towards the earth. The cycle continues till the earth’s surface has no longwave radiation to emit. |
Ques 3: Which of the following chemicals cause water pollution?
- Arsenic
- Copper
- Zinc
Select the correct answer from the following codes
a) Only 1
b) Only 1 and 2
c) Only 2 and 3
d) 1,2 and 3
Ans: d
| Explanation: Metals like lead, zinc, arsenic, copper, mercury, and cadmium in industrial wastewaters adversely affect humans and other animals. arsenic polluted water leads to accumulation of arsenic in the body parts like blood, nails, and hairs causing skin lesions, rough skin, dry and thickening of the skin and ultimately skin cancer. |
Ques 4: With reference to Eutrophication, Which of the following is/are true?
- It is the phenomenon of nutrient enrichment of a water body
- It depletes the water of dissolved oxygen (DO).
- Human activities are mainly responsible for the eutrophication
Select the correct answer from the following codes
a) Only 1
b) Only 1 and 2
c) Only 2 and 3
d) 1,2 and 3
Ans: d
| Explanation: Discharge of domestic waste, agricultural surface runoff, land drainage and industrial effluents in a water body leads to rapid nutrients enrichment in a water body. The excessive nutrient enrichment in a water body encourages the growth of algae, water hyacinth, Phytoplankton, and other aquatic plants. The biological demand for oxygen (BOD) increases with the increase in aquatic organisms. |
Ques 5: The protocol which decided to completely phase out CFC is
a) Cartagena protocol
b) Stockholm Convention
c) Montreal protocol
d) Kyoto protocol
Ans: c
| Explanation: The Montreal Protocol was amended in 1990 where it was decided to completely phase out CFC to prevent ozone layer depletion. |
Ques 6: Biofuels are fuels extracted from plants and crops and these have various advantages. These include
- increasing agricultural diversity.
- reduced use of fertilizers.
- The renewable source of energy.
Select the correct answer using the codes given below.
a) 1 and 3 only
b) 3 only
c) 2 and 3 only
d) 1, 2 and 3
Ans: b
| Explanation: Biofuels may lead to a monoculture where farmers will prefer cultivating such crops that can be used in making biofuels. Fertilizers used in such crops will only increase fertilizer use. Biofuels are renewable sources and this is their advantage compared to non-renewable fossil fuels. Use of Fertilizers: As biofuels are produced from crops and these crops need fertilizers to grow better. The downside of using fertilizers is that they can have harmful effects on the surrounding environment and may cause water pollution. Fertilizers contain nitrogen and phosphorus. They can be washed away from soil to a nearby lake, river or pond. Monoculture: Monoculture refers to practice of producing same crops year after year, rather than producing various crops through a farmer’s fields over time. While, this might be economically attractive for farmers but growing same crop every year may deprive the soil of nutrients that are put back into the soil through crop rotation. Farmers may be tempted to produce crops which are goof for biofuels. |
Ques 7: Fertilizers are added to supply mainly three nutrients – Nitrogen (N), Phosphorous (P), and Potassium (K). Biofertilizers can supply which of these nutrients?
- Nitrogen
- Phosphorous
- Potassium
Select the correct answer using the codes given below.
a) 1 only
b) 1 and 2 only
c) 1 and 3 only
d) 1, 2 and 3
Ans: b
| Explanation: Biofertilizers can provide all three nutrients. |
Ques 8: Which of the following evidence supports the theory of a gradual rise in air temperature and consequent global warming?
- spreading of tropical diseases towards temperate regions.
- downward shifting of snow lines of tropical mountains.
- freezing of permafrost areas.
Select the correct answer using the codes given below.
a) 1 only
b) 1 and 2 only
c) 2 and 3 only
d) 1 and 3 only
Ans: a
| Explanation: Upward shifting of snow lines of tropical mountains and thawing of permafrost areas indicate global warming. The spreading of tropical diseases towards temperate regions signifies that conditions are becoming more tropical due to an increase in temperature. It thus also indicate global warming. |
Ques 9: Health problems associated with indoor air pollution in developing countries is most commonly associated with
a) chlorine gas released from tap water.
b) the use of biofuels for cooking and heating.
c) poor hygiene and sanitation inside the home.
d) the widespread use of pesticides to control disease vectors.
Ans: b
| Explanation: The majority of biofuel that is used for heating is substantial. As wood is the most practical method to heat, houses that use wood-burning stoves rather than gas or electricity. A blend of biodiesel will reduce the emission of both nitrogen and sulphur dioxide. |
Ques 10: Which one of the following pairs is mismatched?
a) fossil fuel burning - release of CO2
b) nuclear power - radioactive wastes
c) solar energy - greenhouse effect
d) biomass burning - release of CO2.
Ans: c
| Explanation Due to heavy industrialization and transportation (modernization), concentration is increasing day by day in the atmosphere. CO2has the capacity for absorbing heat radiations and thus increases the temperature. This increase in global temperature (global warming) is mainly due to CO2 concentration is called the greenhouse effect. Complete combustion of fossil fuels and biomass releases carbon dioxide. Nuclear power plants release radioactive wastes. |
We sincerely hope that the given questions would have helped you in your Prelims preparation. You can also check the below link to keep yourself updated on the latest GK quiz and events.
GK Quiz on Daily Static and Current Events
Topic-wise Important Questions on Environment & Ecology