Environmental Science MCQ – Asked in Previous Years, WBCS Mains

Answer – B. 500 m
Explanation-
▪ The coastal zone extends from the coastline to a distance of 500 meters inland from the high tide line. It is an ecologically sensitive area that includes beaches, dunes, estuaries, wetlands, and other coastal features. The coastal zone is important for the conservation of marine and coastal ecosystems, as well as for sustainable coastal development and protection against natural hazards.

Answer – B. 1998
Explanation-
▪ The Bio-Medical Waste (Management and Handling) Rules, 1998 were notified by the Ministry of Environment and Forests, Government of India on 20th July 1998. These rules govern the generation, collection, segregation, transportation, treatment, and disposal of biomedical waste in India.

▪ The rules were amended in 2003 and 2016. The latest amendment, the Biomedical Waste Management Rules 2016, was notified on 28th March 2016. These rules have stricter provisions than the previous rules and aim to improve the management of biomedical waste in India.

Answer –B. 48 A
Explanation-
▪ Article 48 A of the Indian Constitution was inserted by the 42nd Amendment Act, 1976. It states that the State shall endeavour to protect and improve the environment and to safeguard the forests and wild life of the country.

Answer – C. Radioactive
Explanation-
▪ GM (Geiger-Muller) counter is a device used to detect and measure ionizing radiation, including radioactive particles and rays. It operates on the principle of ionization produced in a gas-filled chamber when radiation passes through it. GM counters are commonly used in applications related to nuclear power plants, radiation monitoring, laboratory research, and radioactive material handling.

Answer – C. Suspended particles
Explanation-
▪ Gravity-settling chambers, also known as settling chambers or sedimentation chambers, are used in industries to remove suspended particles from gas or air streams. These chambers rely on the force of gravity to allow the heavier particles to settle down, separating them from the gas stream.

▪ The settled particles can be collected and disposed of properly, while the purified gas or air is released into the environment. Gravity-settling chambers are effective in reducing particulate matter emissions and improving air quality.

Answer – A. Jatropha
Explanation-
▪ Jatropha (Jatropha curcas) is a tree that is known for yielding biodiesel. The seeds of the Jatropha plant contain oil, which can be extracted and processed to produce biodiesel. Jatropha biodiesel is considered a renewable and environmentally friendly alternative to fossil fuels. The plant is relatively easy to grow, and its oil has properties that make it suitable for use as a fuel in diesel engines.

Answer –B. Infrared region
Explanation-
▪ Greenhouse gases, such as carbon dioxide (CO2) and methane (CH4), emit and absorb radiation within the infrared region of the electromagnetic spectrum. When sunlight reaches the Earth’s surface, it is absorbed and re-emitted as infrared radiation. Greenhouse gases in the atmosphere trap a portion of this infrared radiation, leading to the greenhouse effect and the warming of the Earth’s surface.

Answer – B. Chlorofluorocarbon
Explanation-
▪ Chlorofluorocarbons (CFCs) are the gases used in refrigerators and air conditioners that are known to destroy the ozone layer. CFCs were widely used in the past as refrigerants, propellants in aerosol sprays, and in other industrial applications.

▪ When released into the atmosphere, CFCs rise to the stratosphere, where they undergo a series of chemical reactions that release chlorine atoms. These chlorine atoms catalytically destroy ozone molecules, leading to ozone depletion.

Answer – C. Chemical pesticides
Explanation-
▪ The book ‘Silent Spring’ written by Rachel Carson described the detrimental effects of chemical pesticides, particularly DDT (dichlorodiphenyltrichloroethane), on the environment and wildlife. The book, published in 1962, brought attention to the harmful impacts of indiscriminate pesticide use, including the death of birds, pollution of water bodies, and the disruption of ecosystems. It played a significant role in raising awareness about the need for environmental conservation and the regulation of pesticide use.

Answer – A. High Tide Line
Explanation-
▪ The High Tide Line demarcates the coastal area of the Bay of West Bengal. It refers to the line on the shore up to which the highest level of the tide reaches during spring tide. The High Tide Line is an important boundary used in coastal zone management and environmental planning.