Q.1 Which of the following gases is primarily responsible for global warming?
Oxygen
Carbon dioxide
Nitrogen
Argon
Explanation - Carbon dioxide (CO2) is a major greenhouse gas that traps heat in the atmosphere, contributing to global warming.
Correct answer is: Carbon dioxide
Q.2 What is the main cause of ozone layer depletion?
CO2 emissions
CFCs (Chlorofluorocarbons)
Methane release
Nitrogen oxides
Explanation - CFCs released from refrigerants, aerosols, and industrial processes break down ozone molecules in the stratosphere.
Correct answer is: CFCs (Chlorofluorocarbons)
Q.3 Which of the following is a non-renewable resource?
Wind energy
Coal
Solar energy
Hydropower
Explanation - Coal is a fossil fuel formed over millions of years and cannot be replenished on a human timescale.
Correct answer is: Coal
Q.4 Eutrophication of water bodies is caused by the excessive presence of:
Nutrients like nitrogen and phosphorus
Dissolved oxygen
Salts
Heavy metals
Explanation - Excessive nutrients from fertilizers lead to algal blooms, which deplete oxygen and harm aquatic life.
Correct answer is: Nutrients like nitrogen and phosphorus
Q.5 Which of the following is an effect of acid rain?
Soil acidification
Ozone formation
Global warming
Deforestation
Explanation - Acid rain, caused by sulfur and nitrogen oxides, lowers soil pH and damages plants and aquatic ecosystems.
Correct answer is: Soil acidification
Q.6 Which practice helps in conserving soil fertility?
Deforestation
Crop rotation
Overgrazing
Urbanization
Explanation - Crop rotation replenishes soil nutrients and reduces pest buildup, maintaining soil fertility.
Correct answer is: Crop rotation
Q.7 Which of the following is considered a biodiversity hotspot in India?
Sundarbans
Thar Desert
Himalayan Tundra
Indus Plains
Explanation - The Sundarbans mangrove region is rich in species diversity and considered a biodiversity hotspot.
Correct answer is: Sundarbans
Q.8 Which method is effective for preventing soil erosion on slopes?
Contour farming
Deforestation
Over-irrigation
Monoculture
Explanation - Planting along natural contours slows water runoff and reduces soil erosion.
Correct answer is: Contour farming
Q.9 Which international agreement aims to reduce greenhouse gas emissions?
Kyoto Protocol
Montreal Protocol
Geneva Convention
Stockholm Declaration
Explanation - The Kyoto Protocol is an international treaty to reduce emissions of greenhouse gases responsible for climate change.
Correct answer is: Kyoto Protocol
Q.10 Biological magnification refers to:
Accumulation of toxins in organisms at higher trophic levels
Increase in biodiversity
Growth of algae
Decomposition of organic matter
Explanation - Toxins like pesticides concentrate as they move up the food chain, affecting top predators severely.
Correct answer is: Accumulation of toxins in organisms at higher trophic levels
Q.11 Which of the following is a major source of indoor air pollution?
Burning biomass fuels
Car exhaust
Industrial smokestacks
Volcanic eruption
Explanation - Indoor cooking with wood, dung, or coal releases harmful pollutants that cause indoor air pollution.
Correct answer is: Burning biomass fuels
Q.12 Which of these is a renewable source of energy?
Natural gas
Petroleum
Solar energy
Coal
Explanation - Solar energy is inexhaustible on a human timescale and considered renewable.
Correct answer is: Solar energy
Q.13 Which gas contributes to ozone layer depletion?
Methane
Nitrous oxide
Chlorofluorocarbons (CFCs)
Carbon dioxide
Explanation - CFCs catalyze the breakdown of ozone in the stratosphere, leading to depletion.
Correct answer is: Chlorofluorocarbons (CFCs)
Q.14 Which of the following is NOT an effect of deforestation?
Loss of biodiversity
Increase in soil fertility
Climate change
Flooding
Explanation - Deforestation causes soil erosion and nutrient loss, reducing fertility rather than increasing it.
Correct answer is: Increase in soil fertility
Q.15 Which of the following organisms is often used as a bioindicator for water pollution?
Frogs
Lichens
Fish
Mayflies
Explanation - Mayflies are sensitive to pollutants, and their presence or absence indicates water quality.
Correct answer is: Mayflies
Q.16 Which type of waste is biodegradable?
Plastic bags
Glass bottles
Food scraps
Metal cans
Explanation - Biodegradable waste can be decomposed naturally by microorganisms.
Correct answer is: Food scraps
Q.17 Which of the following is a major consequence of groundwater depletion?
Soil salinization
Floods
Desertification
Acid rain
Explanation - Overuse of groundwater reduces water availability, leading to land degradation and desertification.
Correct answer is: Desertification
Q.18 Integrated Pest Management (IPM) focuses on:
Using only chemical pesticides
Combining biological, cultural, and chemical control methods
Eliminating all pests
Increasing monoculture crops
Explanation - IPM aims to reduce pesticide use and minimize environmental impact by integrating multiple pest control strategies.
Correct answer is: Combining biological, cultural, and chemical control methods
Q.19 Which of the following is an effect of thermal pollution?
Reduced dissolved oxygen in water
Increased soil fertility
Ozone depletion
Eutrophication
Explanation - Discharge of hot water into water bodies reduces oxygen solubility, harming aquatic life.
Correct answer is: Reduced dissolved oxygen in water
Q.20 Which is the largest source of plastic pollution in oceans?
Industrial chemical spills
Fishing nets and packaging materials
Oil spills
Natural debris
Explanation - Discarded plastics from fishing activities and packaging constitute the majority of ocean plastic pollution.
Correct answer is: Fishing nets and packaging materials
Q.21 Which of the following is a greenhouse gas other than CO2?
Oxygen
Methane
Nitrogen
Helium
Explanation - Methane (CH4) traps heat in the atmosphere and contributes to the greenhouse effect.
Correct answer is: Methane
Q.22 Which of the following human activities contributes most to habitat fragmentation?
Afforestation
Urbanization
Organic farming
Wetland conservation
Explanation - Urban expansion breaks continuous habitats into smaller, isolated patches, affecting biodiversity.
Correct answer is: Urbanization
Q.23 Which of the following is a major consequence of oil spills?
Marine biodiversity loss
Ozone depletion
Acid rain
Global warming
Explanation - Oil spills coat marine organisms and habitats, causing death and disruption of ecosystems.
Correct answer is: Marine biodiversity loss
Q.24 Which soil conservation technique involves planting trees to reduce wind erosion?
Shelterbelts
Contour farming
Terracing
Crop rotation
Explanation - Shelterbelts are rows of trees planted to act as windbreaks, preventing soil erosion by wind.
Correct answer is: Shelterbelts
Q.25 Which of the following is considered an invasive species in India?
Water hyacinth
Neem
Bamboo
Mango tree
Explanation - Water hyacinth grows rapidly in water bodies, choking them and affecting native biodiversity.
Correct answer is: Water hyacinth