Why is the depletion of the ozone layer a concern for humans?
- A.It promotes plant growth.
- B.It leads to increased water pollution.
- C.It protects us from harmful radiation.
- D.It increases soil fertility.
Correct answer
Explanation
The correct answer is C, It protects us from harmful radiation. The ozone layer shields us from the Sun's harmful ultraviolet rays, so when it thins, that protection is lost. It lies in the stratosphere, roughly 15 to 35 km above the Earth, and absorbs most of the UV-B and UV-C radiation. More UV reaching the ground means more skin cancer, cataracts and weaker immunity in people, and damage to crops and to plankton in the sea. The main culprits are chlorofluorocarbons (CFCs), once used in refrigerators, air conditioners and aerosol sprays; a single chlorine atom can destroy thousands of ozone molecules. The Montreal Protocol of 1987 phased these chemicals out. A is wrong because extra UV harms plants and lowers crop yields. B is wrong because ozone loss is about radiation, not the pollution of water. D is wrong because it does nothing to make soil more fertile. Exam tip: ozone layer = Earth's sunscreen in the stratosphere; CFCs damage it; Montreal Protocol 1987; World Ozone Day is 16 September.
Practice Questions
View allWhich one of the following is not included in the National Air Quality Index?
- A.Sulphur
- B.Nitrogen dioxide
- C.Lead
- D.Methane
Show answer
Methane is not one of the pollutants used to calculate India's National Air Quality Index. The National Air Quality Index was launched in 2014 under the Swachh Bharat Abhiyan and is run by the Central Pollution Control Board.
Read the full explanation →Which one of the following statements about the National Green Tribunal is not correct?
- A.It was set up in the year 2010.
- B.It is involved in effective and expeditious disposal of cases relating to environmental protection and conservation of forests.
- C.It may consider giving relief and compensation for damages to persons and property.
- D.It is bound by the procedures laid down under the Code of Civil Procedure, 1908.
Show answer
The National Green Tribunal is not bound by the Code of Civil Procedure; it is guided by the principles of natural justice.
Read the full explanation →Consider the following statements about National Wildlife Action Plan (NWAP) of India for 2017-2031:
1. This is the Third National Wildlife Action Plan.
2. The NWAP is unique as this is the first time India has recognized the concerns relating to climate change impact on wildlife.
3. The NWAP has ten components.
Which of the statements given above is/are correct?
- A.1 only
- B.1 and 2 only
- C.2 and 3 only
- D.1, 2 and 3
Show answer
The plan for 2017-2031 is India's third National Wildlife Action Plan and the first to deal with the impact of climate change on wildlife, but it has five components, not ten.
Read the full explanation →Which one of the following methods is not suitable for urban rainwater harvesting?
- A.Rooftop recharge pit
- B.Recharge wells
- C.Gully plug
- D.Recharge trench
Show answer
A gully plug is a small check structure built across a natural gully or stream channel in hilly and rural land, so it has no place in a city.
Read the full explanation →The city of Cartagena, which is famous for Protocol on Biosafety, is located in
- A.Colombia
- B.Venezuela
- C.Brazil
- D.Guyana
Show answer
Cartagena is a port city on Colombia's Caribbean coast, where talks on the biosafety protocol were held in 1999. The Cartagena Protocol on Biosafety is a supplementary agreement to the Convention on Biological Diversity of 1992.
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