Environment MCQ Quiz - Objective Question with Answer for Environment - Download Free PDF

The correct answer is All the statements i, ii, and iii.

Key Points

• Nitrous oxide (N₂O) is a potent greenhouse gas with a global warming potential much higher than carbon dioxide.
• Carbon dioxide (CO₂) is one of the primary greenhouse gases responsible for global warming. It is released through activities like burning fossil fuels and deforestation.
• Methane (CH₄) is another major greenhouse gas, primarily released through agriculture (e.g., livestock digestion), landfills, and the production of oil and gas.
• All three gases—Nitrous oxide, Carbon dioxide, and Methane—contribute significantly to the greenhouse effect, which leads to global warming and climate change.

Important Points

• The greenhouse effect is a natural process that warms the Earth's surface. However, human activities have amplified the effect, leading to climate change.
• Greenhouse gases trap heat in the atmosphere, making the Earth warmer than it would be without them.
• The primary sources of these greenhouse gases are industrial activities, energy production, agriculture, and deforestation.
• Global initiatives like the Paris Agreement aim to reduce greenhouse gas emissions and combat climate change.

Additional Information

• Option 1: "Only the statement ii" is incorrect because both Nitrous oxide and Methane, in addition to Carbon dioxide, are greenhouse gases.
• Option 2: "Statements i and ii only" is incorrect because it excludes Methane, which is also a greenhouse gas.
• Option 3: "Statements ii and iii only" is incorrect because it excludes Nitrous oxide, another significant greenhouse gas.
• Option 4: "All the statements i, ii, and iii" is correct as all three gases mentioned are greenhouse gases contributing to the greenhouse effect.

The correct answer is 5.2.

Key Points

• The average annual net loss of forest has been reduced significantly from 8.3 million hectares in the 1990s to 5.2 million hectares between 2000 and 2010.
• This reduction is attributed to an increase in afforestation efforts, which involve planting trees on lands that previously did not have forests.
• A slight decrease in deforestation activities, which involve the clearing of forests for agriculture or other uses, also contributed to the reduction in net forest loss.
• Natural expansion of forests, where forests regenerate naturally without human intervention, has further helped in reducing the net loss of forest area.

Additional Information

• Afforestation:
  • Afforestation is the process of planting trees on lands that have not been forested for a long time or have never been forested.
  • This practice helps in increasing the forest cover, improving biodiversity, and combating climate change by absorbing carbon dioxide from the atmosphere.
• Deforestation:
  • Deforestation refers to the large-scale removal of forests, primarily for agricultural expansion, urban development, or logging.
  • It leads to the loss of biodiversity, disruption of water cycles, and contributes to climate change due to the release of stored carbon dioxide.
• Natural Expansion of Forests:
  • This occurs when forests regenerate naturally over time without human intervention.
  • Natural expansion can happen due to the abandonment of agricultural lands, reduction in human disturbances, or favorable climatic conditions.
• Net Loss of Forest:
  • The net loss of forest is calculated by subtracting the area of forest gained through afforestation and natural expansion from the area of forest lost due to deforestation.
  • A decrease in net loss indicates positive progress towards forest conservation and sustainable land management practices.

 The war criminals of the Second World War were put to trial in Nuremberg.
Key Points The Nuremberg trials were a series of military tribunals held after World War II by the Allied forces. They were most notable for the prosecution of prominent members of the political, military, and economic leadership of Nazi Germany. The trials were held in the city of Nuremberg, Germany, 1 hence the name
Important Points The Nuremberg Trials took place after the end of World War II (1939-1945). They were conducted by the Allied forces, which included the United States, Great Britain, the Soviet Union, and France.
Military Tribunals: These were not ordinary civilian courts but rather military tribunals, established specifically to deal with the unprecedented crimes committed by the Nazi regime.
Prosecution of Nazi Leaders: The primary focus of the trials was the prosecution of high-ranking Nazi officials. 
Additional Information Pittsburgh is a major city in the United States with its own rich history, it was not considered as a location for the Nuremberg Trials.
St. Petersburg, which was indeed a major city in Russia (and previously, the capital of the Russian Empire). However, St. Petersburg was not the location of the Nuremberg Trials.
Gettysburg is in Pennsylvania, USA. The Nuremberg Trials were held in Nuremberg, Germany. These are two completely different locations. 
Time Period: The Battle of Gettysburg took place in 1863, during the American Civil War.

The correct answer is Asiatic Cheetah.

Key Points

• The Asiatic Cheetah is a subspecies of cheetah found in Iran.
• It is classified as Critically Endangered on the IUCN Red List.
• The population of Asiatic Cheetah has drastically declined due to habitat loss, hunting, and human-wildlife conflict.
• Conservation efforts are ongoing in Iran, the last known habitat of the Asiatic Cheetah.

Additional Information

• Black Buck
  • The Black Buck is a species of antelope found in India, Nepal, and Pakistan.
  • It is classified as Least Concern on the IUCN Red List.
  • The Black Buck is known for its distinctive spiral horns.
  • Conservation efforts have been successful in increasing its population in protected areas.
• Crocodile
  • Crocodiles are large aquatic reptiles found in tropical regions of Africa, Asia, the Americas, and Australia.
  • There are several species of crocodiles, with varying conservation statuses from Least Concern to Critically Endangered.
  • Crocodiles are apex predators and play a crucial role in their ecosystems.
  • Conservation efforts focus on habitat protection and reducing human-wildlife conflict.
• Indian Wild Ass
  • The Indian Wild Ass, also known as the Khur, is a species of wild ass found in the Rann of Kutch in Gujarat, India.
  • It is classified as Near Threatened on the IUCN Red List.
  • The population of the Indian Wild Ass has been increasing due to successful conservation efforts.
  • Habitat protection and anti-poaching measures are key to its conservation.

The correct answer is Dobson

Explanation:

• The ozone layer is a region of Earth's stratosphere that contains a high concentration of ozone (O₃) and protects life on Earth by absorbing most of the sun's harmful ultraviolet (UV) radiation.
• The thickness of the ozone layer is measured in Dobson Units (DU), which is a unit of measurement that describes the amount of ozone in a column of the atmosphere.
• The thickness of the ozone in a column of air from the ground to the top of the atmosphere is measured in terms of Dobson units (DU).
• One Dobson unit represents a layer of ozone that would be 0.01 millimeters thick under standard temperature and pressure.
• This unit is named after G. M. B. Dobson, who was a pioneer in the study of atmospheric ozone.

Other Options:

• Joule: This is a unit of energy in the International System of Units (SI). One Joule is the amount of energy transferred or work done when applying a force of one newton over a distance of one meter. 
• Newton: This is the SI unit of force. One Newton is the force required to accelerate a mass of one kilogram at a rate of one meter per second squared. 
• Decibels: This is a unit used to measure the intensity of sound.

The correct answer is i - b, ii - c, iii - d, iv - a.

Key Points

The trophic levels represent the hierarchical levels in an ecological food chain, indicating the position of organisms based on their feeding relationships. Here's the explanation for the correct match:

• First trophic level - phytoplankton:
  • The first trophic level typically consists of primary producers that convert sunlight into energy through photosynthesis.
  • Phytoplankton are microscopic plants that form the base of aquatic food chains.
• Second trophic level - zooplankton:
  • The second trophic level comprises primary consumers that feed on the primary producers.
  • Zooplankton, which includes tiny animals, consume phytoplankton, placing them at the second trophic level.
• Third trophic level - fishes:
  • The third trophic level involves secondary consumers that feed on primary consumers.
  • In aquatic ecosystems, fishes are often positioned at the third trophic level as they consume zooplankton or other smaller organisms.
• Fourth trophic level - human:
  • The fourth trophic level represents tertiary consumers, which are higher-order predators.
  • Humans, being omnivores or carnivores, are often placed at the fourth trophic level in food chains when they consume animals from lower trophic levels.​ 

The correct answer is sulphur hexafluoride.Key Points

• Sulphur hexafluoride is a synthetic fluorinated gas with an extremely stable molecular structure, making it the most potent greenhouse gas ever found.
• It has a global warming potential of 23,500 times that of CO₂, meaning that it traps 23,500 times more heat in the atmosphere than CO₂.
• Sulphur hexafluoride is commonly used in electrical transmission and distribution equipment, as well as in the production of magnesium and aluminium.

Additional Information

• Hydrogen fluoride (option 1) is a highly corrosive gas used in the production of fluorine compounds, including sulphur hexafluoride.
• Sodium monofluorophosphate (option 2) is a salt commonly used in toothpaste to prevent tooth decay.
• Calcium fluoride (option 4) is a mineral found in teeth and bones and is also used in the production of aluminium.

The correct answer is Section 5 A.

Key Points

• The National Board for Wildlife (NBWL) -
  • It is constituted by the Central Government under Section 5 A of the Wildlife (Protection) Act, 1972 (WLPA). 
  • It may, at its discretion, constitute a Standing Committee under sub-section (1) of Section 5B.

Additional Information

• ​National Board for Wildlife (NBWL) -
  • It was formed in the year 2003 under the Wildlife (Protection) Act, of 1972.
  • It acts as the apex body in matters relating to forest ecology.
  • This body reviews matters relating to wildlife and construction or other projects around national parks and sanctuaries.
  • It is chaired by the Prime Minister.

The correct answer is Low level ozone (or tropospheric ozone) is an atmospheric pollutant.

Key Points

• "Low-level ozone (or tropospheric ozone) is an atmospheric pollutant", this statement is true.
  • Tropospheric ozone is a short-lived climate pollutant with an atmospheric lifetime of hours to weeks.
  • It does not have any direct emissions sources, rather it is a secondary gas formed by the interaction of sunlight with hydrocarbons.
  • The conversion of Ozone to oxygen is an exothermic reaction.
  • It means when ozone gets converted into oxygen, heat is released.​

Additional Information

• Ozone (O3) is a triatomic molecule consisting of three oxygen atoms. 
• It is an oxygen allotrope.
• It has three electron groups around the central oxygen, and so has the trigonal planar electron geometry.
• It has one double bond and one single bond in its Lewis structure.

The correct answer is option 1 that is organic matter.

Concept:

• The concentration of hydrogen ions in the soil solution is measured by soil pH, which also serves as a gauge for the acidity or alkalinity of the soil.
• Some plants do best in neutral (pH 7) soil, while others do better in slightly acidic (pH 7) or slightly alkaline (pH > 7) soil.
• The ability of a plant to absorb nutrients can be hampered when the pH of the soil is too severe (either too acidic or too basic), which can have a detrimental effect on growth and productivity.
• Many minerals, including iron, manganese, and phosphorus, become less accessible for plant absorption in strongly alkaline or basic soils (pH significantly more than 7).

Explanation:

• The pH of the soil can be lowered (making it less alkaline) and overall soil health can be improved by adding organic matter, such as compost or well-rotted manure.
• These additives improve the activity of the soil's producing organic acid-producing organisms, which can aid in balancing the soil's alkalinity.
• Note that adding materials like quicklime or calamine solution would actually increase the soil's alkalinity, making it more basic rather than less. These choices would therefore not be suitable.
• It is typically advised that soil be tested to ascertain its current pH and nutrient levels before to making any modifications. This can assist in determining which adjustments, if any, would be most helpful.

Hence,the correct option is organic matter.

Key Points

• Desertification refers to the process by which an area is converted to a desert, which is marked by dry-arid land and lack of vegetation.
• Soil erosion is the removal of the top layer of soil.
• The topmost layer of the soil is the most fertile and may be removed in two ways:
  • Natural - It is extremely slow removal of topsoil due to rainwater or wind. 
  • Anthropogenic - It is caused by various human activities.
• Some of the anthropogenic causes include:
  • Overcultivation - This depletes the soil fertility beyond repair, leading to desertification.
  • Unrestricted grazing - Overgrazing in grasslands may also loosen up the roots of grasses, allowing soil erosion.
  • Deforestation - This refers to the cutting of forest trees, the roots of which hold the soil together.
  • Poor irrigation - This increases water run-offs in agricultural fields, which increases soil erosion.

The given activities all lead to soil erosion and desertification.

Hence, the correct answer is option 2.

The correct answer is Tamil Nadu.

Key Points

• Tamil Nadu has launched the "Tamil Nadu Elephant Death Audit Framework," a first-of-its-kind project in India, to better account for elephant fatalities by documenting their causes.
• At the State Wildlife Board meeting, Chief Minister MK Stalin made this announcement.
• The framework aims to achieve three key goals:
  • firstly, it provides a systematic standard protocol for conducting post-mortems to identify the cause(s) of elephant deaths;
  • secondly, it investigates and analyzes the circumstances surrounding elephant deaths that could have been prevented; and
  • thirdly, it develops corrective measures to prevent unnatural and preventive deaths by conducting periodic death audits and tracking these over time.

Additional Information

• Elephants in India: According to Project Elephant's 2017 census, India is home to an estimated 29,964 wild Asian elephants, making it the country with the highest population.
  • Approximately 60% of the species' global population consists of it.
  • Karnataka has the highest number of elephants, followed by Assam and Kerala.
• The Indian Wild Life Protection Act of 1972 designates elephants as National Heritage animals and provides them with protection under the Schedule I species.
  • With the primary goal of restoring elephant habitats and mitigating the suffering of elephants and the human population, the Indian government initiated "Project Elephant" in 1991–1992, a Ministry of Environment, Forests & Climate Change centrally sponsored scheme.
  • Its goals included addressing the issue of human-animal conflict and offering financial and technical support to the Indian states that make up the elephant range in order to safeguard the elephants, their habitats, and their corridors.
  • It also aimed to advance the welfare of elephants kept in captivity.
  • The following goals guided the launch of Project Elephant (PE): 
    • To protect elephants, their habitat & corridors
    • To address issues of man-animal conflict
    • Welfare of captive elephants

Concept: 

• Particulate matters refer to a mixture of solid particles and liquid droplets found in the air.
• There are several ways of removing particulate matter; however, the most widely used is the electrostatic precipitator.

Explanation:  

• The scrubber removes harmful materials from industrial exhaust gases before they are released into the environment.
• Electrostatic precipitator consists of electrode wires that are maintained at several thousand volts, which produce a corona that releases electrons.
• Electrons get attached to dust particles giving them a net negative charge.
• The collecting plates are grounded and attract charged dust particles.

Statement I: In a scrubber, the exhaust from the thermal plant is passed through the electric wires to charge the dust particles. 

The limestone present in the slurry of scrubber removes SO₂ from the exhaust. Therefore statement I is incorrect.

Statement II:

Particulate matter (PM 2.5) can not be removed by a scrubber but can be removed by an electrostatic precipitator.

An electrostatic precipitator is the most effective device to remove 99% of particulate matter, ‘even PM 2.5’ present in the exhaust. Therefore statement II is correct.

Thus, option 1 is the correct answer.

 

The correct answer is Carbon dioxide.

Key Points

• GREENHOUSE EFFECT:
  • The rays coming from the sun get reflected after striking the earth's surface. Certain gases do not allow the reflected (infrared) rays to escape the earth's atmosphere and thus the heat gets trapped. This phenomenon is known as the greenhouse effect and the gases involved are termed as greenhouses gases.
  • The heat trapped increases the temperature of the earth and this phenomenon is known as global warming.
  • Causes of Greenhouse Effect:
    • Burning of Fossil Fuels
    • Deforestation
    • Farming
    • Industrial Waste and Landfills
  • Effects of Greenhouse Effect:
    • Global Warming
    • Depletion of Ozone Layer
    • Smog and Air Pollution
    • Acidification of Water Bodies
  • The prominent greenhouse gases are - Water Vapour, Carbon dioxide, Methane, Nitrous oxide, Ozone, Chlorofluorocarbons, and Hydrofluorocarbons.
  • The major cause of global warming is the emission of greenhouse gases.
  • 72% of the totally emitted greenhouse gases is carbon dioxide (CO2), 18% Methane, and 9% Nitrous oxide (NOx).
  • Carbon dioxide emissions, therefore, are the most important cause of global warming.
• WATER VAPOUR (H2O):
  • As evident from the above table, it is the most abundant greenhouse gas present in the atmosphere.
  • Warmer air has the capacity of holding more water vapor, which traps more heat. Due to this, a positive feedback loop gets created.

• CARBON DIOXIDE (CO2):
  • Events like volcanic eruptions, forest fires, burning of fossil fuels lead to an increase in the carbon dioxide concentration in the atmosphere.
• METHANE (CH4):
  • Though its concentration in the atmosphere is very low, its contribution is approximately 9% in greenhouse gases.
  • It has more heating capacity as compared to water vapor and carbon dioxide.

Concept:

• Ocean thermal energy refers to the method of using the temperature difference between the deep parts of the ocean which are cold and the shallow part of the ocean to run a heat engine.
• Ocean thermal energy conversion is an electricity generation system.

Explanation:

• The water at the surface of the ocean or sea is heated by the sun.
• While the deeper section is relatively cold.
• This difference in temperature is exploited to obtain energy in ocean thermal energy conversion plants.
• The warm surface water is used to boil a volatile liquid like ammonia.
• The vapor of a liquid is then used to run the turbine of a generator.
• The cooled water from the depth of the ocean is pumped up and condensed vapor again into a  liquid.

Thus, the correct answer is a volatile liquid.