TCS/ TPS - Grade-II Mains Examination
(GS Paper-1) Fully Solved

Very Short Answer Type Questions:                                                                               (2 marks each)

1. Who initiated the ‘Man and Biosphere’ program?

Ans: Man and the Biosphere Programme (MAB) was initiated by UNESCO in 1971 with a primary objective to establish a scientific basis for the improvement of relationships between people and their environment.

2. Nitrogen and hydrocarbons react in the presence of sunlight. Name the secondary pollutants produced in the reaction.

Ans: Secondary Pollutants: They are produced as a result of chemical interactions between primary pollutants and different atmospheric compounds in the form of radiations from the sun.

Secondary pollutants produced by the reaction of Nitrogen and Hydrocarbons in the presence of sunlight are:

  1. Smog- Produced by complex reaction between nitrogen oxides and a wide range of hydrocarbons activated by sunlight. Example- Photochemical Smog.
  1. Ozone (O3) – Nitrogen dioxide+ Sunlight+ Hydrocarbons.

3. What do the jet airplanes and refrigerators have in common that has contributed to pollution?

Ans: Jet airplanes release CO2 while refrigerators release CFCs and both are powerful Green House Gases. CFCs cause ozone layer depletion while the increased concentration of Co2 results in global warming which further escalates the problem of pollution on the Earth.

4. Where is the headquarters of the United Nations Environmental program?

Ans: The Stockholm conference of 1972 proposed a new UN agency, the United Nations Environment Programme (UNEP) with primary responsibility to formulate and implement all Treaties to reduce the depletion of ozone.

It is headquartered in Nairobi, Kenya.

5. Biological diversity is relatively greater in the tropics. Give two reasons.

Ans: Biological diversity is relatively greater in topics because –

  1. Tropical latitudes receive more solar energy than temperate regions, which leads to high productivity and high species diversity.
  2. Tropical regions have fewer seasonal variations and have a more or less constant environment which promotes niche specialization and thus, results in species richness.


Short Answer Type Questions:                                                                                 (5 marks each)

1. What would happen if there is no CO2, in the earth’s atmosphere?

Ans: CO2 in moderate quantity is an essential element to support life on Earth. In the total absence of CO2, the following possibilities are imminent:

  1. The earth will lose the capacity to retain heat and the temperature of the earth will fall severely after sunset.
  2. The Earth will eventually turn into a non-habitable harsh cold desert for a wide range of species.
  3. Thousands of species will become extinct.
  4. Plant-based life is impossible in absence of CO2
  5. Without plants, oxygen will also become absent and human existence would be impossible.

2. Differentiate between endangered and threatened species.


Endangered Species

Threatened species

1. Endangered species are those plants and animals that have become so rare they are in danger of becoming extinct.

1. Threatened species are plants and animals that are likely to become endangered within the foreseeable future throughout all or a significant portion of their range.

2. Endangered species are at the brink of extinction now.

3. Any endangered species will not survive without direct interventions(through different schemes and programs).

2. Threatened species are likely to be on the brink shortly.

3. A threatened species might bounce back without direct intervention as they don’t face any immediate face of extinction

3. Ex- Siberian Tiger, Brown Spider Monkey, Mexican Wolf, etc.

3. Ex-Amur Leopard, Cross River Gorilla, Black Rhino

3. Give a brief account of the impact of global climate change on human health.

Ans: Climate change affects the social and environmental determinants of health such as clean air, safe drinking water, sufficient food, and secure shelter. Between 2030 and 2050, climate change is expected to cause approximately 250000 additional deaths per year, from malnutrition, malaria, diarrhea, and heatstroke.

Impact on human health:

  1. An adverse change in the social and environmental determinants of human health is bound to create a health hazard for human beings
  2. Rising Temperatures (Extreme heat)- It may directly lead to deaths from cardiovascular and respiratory disease, particularly among elderly people. High temperatures also raise the levels of ozone and other pollutants in the air that further exacerbate cardiovascular and respiratory diseases.
  3. Climate change makes the Earth more prone to natural disasters and extreme weather patterns (Heatwave, Cold-Wave, Drought, Cloudburst, etc.)
  4. Variation in rainfall patterns is bound to affect the supply of fresh water and scarcity of clean water will further expose humans to several illnesses.
  5. Flooding contaminates freshwater supplies, heightens the risk of water-borne diseases, and creates breeding grounds for disease-carrying insects.

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