Comprehensive Ecology and Environment MCQs for SLST and Competitive Exam Preparation

Which of the following is an example of an autotroph?
a) Herbivore
b) Carnivore
c) Plant
d) Fungi
Answer: c) Plant

Which of the following is not a part of the nitrogen cycle?
a) Nitrogen fixation
b) Denitrification
c) Photosynthesis
d) Nitrification
Answer: c) Photosynthesis

What is the primary cause of acid rain?
a) Carbon dioxide
b) Sulfur dioxide and nitrogen oxides
c) Chlorofluorocarbons (CFCs)
d) Methane
Answer: b) Sulfur dioxide and nitrogen oxides

What is the main consequence of deforestation?
a) Decrease in biodiversity
b) Increase in atmospheric oxygen
c) Increased rainfall
d) Decrease in soil erosion
Answer: a) Decrease in biodiversity

Which of the following is a major greenhouse gas?
a) Oxygen
b) Carbon dioxide
c) Nitrogen
d) Argon
Answer: b) Carbon dioxide

The term ‘green revolution’ refers to:
a) A movement for reducing carbon emissions
b) The use of technology and new farming techniques to increase crop production
c) The shift from organic to synthetic farming
d) The conservation of forest resources
Answer: b) The use of technology and new farming techniques to increase crop production

Which of the following is a renewable resource?
a) Coal
b) Natural gas
c) Wind energy
d) Petroleum
Answer: c) Wind energy

In an energy pyramid, energy decreases as you move:
a) From top to bottom
b) From bottom to top
c) In a circular manner
d) In a zigzag manner
Answer: b) From bottom to top

The process by which plants convert carbon dioxide and water into glucose using sunlight is known as:
a) Respiration
b) Photosynthesis
c) Transpiration
d) Decomposition
Answer: b) Photosynthesis

Which of the following is the major cause of ozone depletion?
a) Carbon emissions
b) Chlorofluorocarbons (CFCs)
c) Nitrous oxide
d) Sulfur dioxide
Answer: b) Chlorofluorocarbons (CFCs)

Which of the following is not a renewable energy source?
a) Solar energy
b) Wind energy
c) Biomass
d) Nuclear energy
Answer: d) Nuclear energy

A species that can live and reproduce in only one specific type of environment is called:
a) Endemic
b) Exotic
c) Native
d) Invasive
Answer: a) Endemic

The main function of decomposers in an ecosystem is to:
a) Produce energy
b) Break down dead organisms
c) Consume plants
d) Control pest populations
Answer: b) Break down dead organisms

Which of the following is an example of an abiotic factor in an ecosystem?
a) Plants
b) Animals
c) Soil
d) Bacteria
Answer: c) Soil

The term ‘biodiversity’ refers to:
a) The variety of life forms on Earth
b) The number of animals in a specific habitat
c) The population size of a species
d) The richness of an ecosystem
Answer: a) The variety of life forms on Earth

What is the most common greenhouse gas produced by human activities?
a) Nitrous oxide
b) Methane
c) Carbon dioxide
d) Ozone
Answer: c) Carbon dioxide

Which of the following is the largest contributor to global warming?
a) Methane emissions
b) Deforestation
c) Carbon dioxide emissions from fossil fuels
d) Urbanization
Answer: c) Carbon dioxide emissions from fossil fuels

Which of the following is an example of an invasive species?
a) Bengal Tiger
b) European Starling
c) American Bison
d) Kangaroo
Answer: b) European Starling

The term ‘carbon footprint’ refers to:
a) The amount of carbon in the soil
b) The total amount of carbon dioxide emitted by human activities
c) The number of trees in a forest
d) The natural production of carbon in ecosystems
Answer: b) The total amount of carbon dioxide emitted by human activities

The concept of ‘sustainable development’ is based on the balance between:
a) Economic growth and social justice
b) Economic growth and environmental protection
c) Social equity and environmental protection
d) All of the above
Answer: d) All of the above

The process by which plants release water vapor into the atmosphere is called:
a) Photosynthesis
b) Respiration
c) Transpiration
d) Evaporation
Answer: c) Transpiration

Which of the following ecosystems is characterized by low precipitation and extreme temperature fluctuations?
a) Tundra
b) Desert
c) Grassland
d) Temperate forest
Answer: b) Desert

A food web is:
a) A linear feeding relationship
b) A network of interconnected food chains
c) A list of trophic levels
d) A cycle of nutrient exchange
Answer: b) A network of interconnected food chains

In an energy pyramid, the largest amount of energy is found at:
a) The primary producer level
b) The herbivore level
c) The carnivore level
d) The decomposer level
Answer: a) The primary producer level

The term ‘biomagnification’ refers to:
a) The increase in biomass of primary producers
b) The process by which chemicals become more concentrated at higher trophic levels
c) The loss of energy in an ecosystem
d) The accumulation of nitrogen in the soil
Answer: b) The process by which chemicals become more concentrated at higher trophic levels

Which of the following is a characteristic of biodiversity hotspots?
a) They are located in arctic regions
b) They contain a high level of endemic species
c) They have no endangered species
d) They are sparsely populated areas
Answer: b) They contain a high level of endemic species

The term ‘extinction vortex’ refers to:
a) The process of species evolving
b) A series of factors that increase the likelihood of a species becoming extinct
c) The area where extinct species are preserved
d) A rapid increase in population of an endangered species
Answer: b) A series of factors that increase the likelihood of a species becoming extinct

The International Union for Conservation of Nature (IUCN) uses which category to classify species that are at risk of extinction?
a) Vulnerable
b) Endangered
c) Critically Endangered
d) All of the above
Answer: d) All of the above

Which of the following is the main factor contributing to habitat fragmentation?
a) Climate change
b) Human activities like agriculture and urbanization
c) Natural disasters
d) Overpopulation of species
Answer: b) Human activities like agriculture and urbanization

The study of interactions between organisms and their environment is called:
a) Genetics
b) Ecology
c) Evolution
d) Biogeography
Answer: b) Ecology

In which of the following biomes do trees lose their leaves during winter to conserve water?
a) Tropical rainforest
b) Tundra
c) Temperate deciduous forest
d) Desert
Answer: c) Temperate deciduous forest

What is the main difference between primary and secondary succession?
a) Primary succession occurs in areas where soil is already present
b) Secondary succession occurs after a disturbance in an area that previously supported life
c) Primary succession occurs after forest fires
d) Secondary succession leads to a climax community faster than primary succession
Answer: b) Secondary succession occurs after a disturbance in an area that previously supported life

Which of the following is an example of an r-strategist?
a) Elephant
b) Deer
c) Frog
d) Whale
Answer: c) Frog

The term ‘food chain’ refers to:
a) A network of feeding relationships in an ecosystem
b) The sequence of organisms eating one another in an ecosystem
c) A list of trophic levels
d) A plant’s nutrient intake system
Answer: b) The sequence of organisms eating one another in an ecosystem

Which of the following factors can limit the growth of a population in an ecosystem?
a) Availability of resources
b) Habitat space
c) Predation
d) All of the above
Answer: d) All of the above

The Kyoto Protocol aims to:
a) Prevent biodiversity loss
b) Reduce greenhouse gas emissions
c) Promote renewable energy
d) Conserve water resources
Answer: b) Reduce greenhouse gas emissions

Which of the following is a non-renewable resource?
a) Wind energy
b) Solar energy
c) Fossil fuels
d) Biomass
Answer: c) Fossil fuels

The ‘Forest Conservation Act’ of India was passed in which year?
a) 1972
b) 1980
c) 1990
d) 2000
Answer: b) 1980

The term ‘sustainable development’ was first introduced in the report:
a) Global 2000 Report
b) The Brundtland Report
c) The Kyoto Protocol
d) The Paris Agreement
Answer: b) The Brundtland Report

The Chipko movement was initiated by:
a) Medha Patkar
b) Sunderlal Bahuguna
c) Baba Amte
d) Vandana Shiva
Answer: b) Sunderlal Bahuguna

Which of the following is an example of a herbivore?
a) Lion
b) Elephant
c) Wolf
d) Hawk
Answer: b) Elephant

The ozone layer is important because it:
a) Reduces global warming
b) Protects life on Earth from harmful UV radiation
c) Helps plants grow faster
d) Regulates the water cycle
Answer: b) Protects life on Earth from harmful UV radiation

What is the primary purpose of a national park?
a) Commercial use of resources
b) Conservation of biodiversity
c) Industrial development
d) Expansion of urban areas
Answer: b) Conservation of biodiversity

Which of the following is a non-renewable resource?
a) Solar energy
b) Coal
c) Wind energy
d) Geothermal energy
Answer: b) Coal

The primary role of producers in an ecosystem is to:
a) Break down organic matter
b) Consume other organisms
c) Produce food through photosynthesis
d) Regulate water cycles
Answer: c) Produce food through photosynthesis

The main purpose of conservation biology is to:
a) Improve agricultural productivity
b) Restore habitats for endangered species
c) Protect humans from natural disasters
d) Promote industrial growth
Answer: b) Restore habitats for endangered species

Which of the following ecosystems is most vulnerable to climate change?
a) Tropical rainforest
b) Desert
c) Tundra
d) Grassland
Answer: c) Tundra

Which of the following is a significant environmental impact of deforestation?
a) Increased water storage
b) Loss of biodiversity
c) Increase in soil fertility
d) Rise in oxygen levels
Answer: b) Loss of biodiversity

What does the term “carbon sequestration” refer to?
a) The process of burning fossil fuels
b) The storage of carbon in soil and vegetation
c) The destruction of the ozone layer
d) The release of carbon dioxide into the atmosphere
Answer: b) The storage of carbon in soil and vegetation

The term “sustainable agriculture” refers to farming practices that:
a) Focus on increasing production without considering environmental impacts
b) Use only chemical fertilizers
c) Prioritize long-term environmental health and resource conservation
d) Are limited to small-scale farming only
Answer: c) Prioritize long-term environmental health and resource conservation

Which of the following is a primary cause of the loss of biodiversity?
a) Overfishing
b) Pollution
c) Habitat destruction
d) All of the above
Answer: d) All of the above

The term “endangered species” refers to organisms that:
a) Are extinct in the wild
b) Are at risk of becoming extinct in the near future
c) Are found in large populations
d) Have successfully adapted to urban environments
Answer: b) Are at risk of becoming extinct in the near future

Which of the following is a key principle of ecological economics?
a) Maximizing short-term profits
b) Sustainable use of resources for future generations
c) Promoting rapid industrialization
d) Minimizing the role of government regulations
Answer: b) Sustainable use of resources for future generations

In an ecosystem, which of the following would be considered a secondary consumer?
a) Grasshopper
b) Deer
c) Frog
d) Hawk
Answer: c) Frog

Which of the following is a consequence of global warming?
a) Decreased sea levels
b) Decreased frequency of storms
c) Melting of polar ice caps
d) Increase in soil fertility
Answer: c) Melting of polar ice caps

The practice of planting trees to combat climate change is known as:
a) Afforestation
b) Reforestation
c) Desertification
d) Deforestation
Answer: a) Afforestation

What is the process of nutrient cycling in an ecosystem?
a) The movement of nutrients through producers, consumers, and decomposers
b) The process of energy flow through an ecosystem
c) The movement of energy from one trophic level to the next
d) The transformation of one chemical element into another
Answer: a) The movement of nutrients through producers, consumers, and decomposers

Which of the following is a method of in-situ conservation?
a) Seed bank
b) Botanical garden
c) Wildlife sanctuary
d) Zoo
Answer: c) Wildlife sanctuary

The largest contributor to marine pollution is:
a) Overfishing
b) Plastic waste
c) Oil spills
d) Pesticide runoff
Answer: b) Plastic waste

Which of the following is not a direct result of overpopulation?
a) Overconsumption of resources
b) Increased waste production
c) Decreased competition for resources
d) Habitat destruction
Answer: c) Decreased competition for resources

The concept of ‘biomagnification’ refers to:
a) The increase in biodiversity as you move up the food chain
b) The increase in toxic substances as they move up the food chain
c) The decrease in biodiversity as a result of pollution
d) The increase in ecosystem services as you move up the food chain
Answer: b) The increase in toxic substances as they move up the food chain

Which of the following is an example of a mutualistic relationship?
a) Predator and prey
b) Parasite and host
c) Bee and flower
d) Herbivore and plant
Answer: c) Bee and flower

The term “bioaccumulation” refers to:
a) The process of increasing biodiversity
b) The accumulation of toxins in an organism’s body over time
c) The process of nutrient recycling in ecosystems
d) The increase in population size of a species
Answer: b) The accumulation of toxins in an organism’s body over time

What is the primary goal of sustainable development?
a) Maximizing economic growth at the cost of the environment
b) Ensuring that natural resources are used at a rate that does not deplete them
c) Increasing global population
d) Expanding industrialization in urban areas
Answer: b) Ensuring that natural resources are used at a rate that does not deplete them

Which of the following is a characteristic of a tropical rainforest?
a) High biodiversity
b) Low rainfall
c) Low temperatures
d) Short growing season
Answer: a) High biodiversity

Which of the following is a key factor that determines the climate of an area?
a) Latitude
b) Altitude
c) Proximity to water
d) All of the above
Answer: d) All of the above

A decrease in the size of the ozone layer leads to:
a) Increased global temperatures
b) Decreased UV radiation reaching Earth
c) Increased growth of phytoplankton
d) Decreased sea level rise
Answer: a) Increased global temperatures

What is the greenhouse effect?
a) The cooling of Earth’s surface due to cloud cover
b) The trapping of heat in the atmosphere by certain gases
c) The process by which plants absorb carbon dioxide
d) The reflection of heat back into space
Answer: b) The trapping of heat in the atmosphere by certain gases

Which of the following is an invasive species that poses a threat to native ecosystems?
a) Cheetah
b) European Starling
c) Bengal Tiger
d) Panda
Answer: b) European Starling

The term “habitat fragmentation” refers to:
a) The creation of new ecosystems
b) The splitting of large habitats into smaller, isolated patches
c) The increase in species population size
d) The destruction of aquatic ecosystems
Answer: b) The splitting of large habitats into smaller, isolated patches

Which of the following is not a renewable resource?
a) Wind
b) Solar energy
c) Natural gas
d) Biomass
Answer: c) Natural gas

The process by which water vapor turns into liquid water is known as:
a) Evaporation
b) Condensation
c) Precipitation
d) Transpiration
Answer: b) Condensation

The Kyoto Protocol aims to:
a) Increase industrial production
b) Reduce greenhouse gas emissions
c) Increase deforestation
d) Promote nuclear energy
Answer: b) Reduce greenhouse gas emissions

Which of the following best defines “biodiversity”?
a) The number of different species in an area
b) The variety of habitats in a region
c) The diversity of ecosystems on Earth
d) All of the above
Answer: d) All of the above

The major source of nitrogen for plants comes from:
a) Rocks
b) Atmosphere
c) Soil bacteria
d) Water bodies
Answer: c) Soil bacteria

The process by which plants release water vapor through their leaves is called:
a) Photosynthesis
b) Respiration
c) Transpiration
d) Evaporation
Answer: c) Transpiration

Which of the following is a direct effect of deforestation?
a) Increased carbon sequestration
b) Reduced biodiversity
c) Increase in water availability
d) Cooling of the Earth’s surface
Answer: b) Reduced biodiversity

Which of the following is an example of an abiotic factor in an ecosystem?
a) Plants
b) Animals
c) Temperature
d) Fungi
Answer: c) Temperature

Which of the following is the largest contributor to global warming?
a) Solar radiation
b) Greenhouse gas emissions from fossil fuels
c) Deforestation
d) Volcanic activity
Answer: b) Greenhouse gas emissions from fossil fuels

Which of the following is an example of ex-situ conservation?
a) Biosphere reserves
b) Zoos
c) National parks
d) Wildlife sanctuaries
Answer: b) Zoos

The main cause of soil erosion is:
a) Wind
b) Water
c) Human activities
d) All of the above
Answer: d) All of the above

Which of the following gases is primarily responsible for acid rain?
a) Carbon dioxide
b) Nitrogen oxide
c) Sulfur dioxide
d) Oxygen
Answer: c) Sulfur dioxide

Which of the following is a characteristic of desert ecosystems?
a) High rainfall
b) Low temperatures
c) Low biodiversity
d) Abundant vegetation
Answer: c) Low biodiversity

What is the primary function of decomposers in an ecosystem?
a) Producing food for primary consumers
b) Breaking down dead organisms and recycling nutrients
c) Capturing solar energy
d) Preying on herbivores
Answer: b) Breaking down dead organisms and recycling nutrients

What is the term for the process by which organisms with favorable traits are more likely to survive and reproduce?
a) Genetic drift
b) Natural selection
c) Mutation
d) Genetic variation
Answer: b) Natural selection

Which of the following is an example of an autotroph?
a) Deer
b) Lion
c) Mushroom
d) Tree
Answer: d) Tree

What is the largest biome on Earth?
a) Tropical rainforest
b) Tundra
c) Boreal forest (Taiga)
d) Ocean
Answer: d) Ocean

The Green Revolution is associated with which of the following?
a) Conservation of water
b) Development of high-yielding crop varieties
c) Deforestation for agricultural use
d) Protection of wildlife species
Answer: b) Development of high-yielding crop varieties

The process by which organisms colonize a new habitat is called:
a) Immigration
b) Emigration
c) Succession
d) Extinction
Answer: c) Succession

Which of the following is the primary greenhouse gas responsible for global warming?
a) Oxygen
b) Methane
c) Nitrous oxide
d) Carbon dioxide
Answer: d) Carbon dioxide

Which of the following is a major factor in the loss of biodiversity?
a) Habitat destruction
b) Reduced food production
c) Overpopulation
d) Genetic modification of crops
Answer: a) Habitat destruction

Which of the following ecosystems has the highest biodiversity?
a) Desert
b) Tundra
c) Tropical rainforest
d) Grassland
Answer: c) Tropical rainforest

The process by which water is absorbed by plants from the soil is called:
a) Transpiration
b) Absorption
c) Evaporation
d) Percolation
Answer: b) Absorption

The energy flow in an ecosystem is:
a) Linear
b) Circular
c) One-way
d) Bi-directional
Answer: c) One-way

Which of the following best defines a “keystone species”?
a) A species that is abundant in an ecosystem
b) A species that is at the top of the food chain
c) A species whose presence and role in an ecosystem has a disproportionate effect on the ecosystem
d) A species that is always herbivorous
Answer: c) A species whose presence and role in an ecosystem has a disproportionate effect on the ecosystem

The “tragedy of the commons” refers to:
a) The overuse of shared resources due to individual self-interest
b) The protection of common resources for public use
c) The depletion of resources through government regulations
d) The ethical responsibility to share resources equally
Answer: a) The overuse of shared resources due to individual self-interest

Which of the following is a key feature of a wetland ecosystem?
a) High temperatures
b) High salinity
c) Presence of standing water
d) Limited biodiversity
Answer: c) Presence of standing water

Which of the following is an example of a density-dependent factor that affects population size?
a) Flooding
b) Earthquake
c) Availability of food
d) Extreme temperatures
Answer: c) Availability of food

What is the main reason for the depletion of the ozone layer?
a) Increased carbon emissions
b) Release of chlorofluorocarbons (CFCs)
c) Deforestation
d) Overuse of fossil fuels
Answer: b) Release of chlorofluorocarbons (CFCs)

The process by which carbon moves through the environment is called:
a) Nitrogen cycle
b) Phosphorus cycle
c) Water cycle
d) Carbon cycle
Answer: d) Carbon cycle

Which of the following is an example of a biotic factor in an ecosystem?
a) Temperature
b) Water
c) Soil
d) Predation
Answer: d) Predation

Which human activity contributes the most to global deforestation?
a) Urbanization
b) Agricultural expansion
c) Mining
d) Tourism
Answer: b) Agricultural expansion

Which of the following is a consequence of overgrazing by livestock?
a) Soil erosion
b) Increased soil fertility
c) Increased plant growth
d) Water purification
Answer: a) Soil erosion

What is the primary cause of ocean acidification?
a) Increase in the number of marine organisms
b) Excessive carbon dioxide in the atmosphere
c) Increased levels of nitrates in the ocean
d) Decreased levels of oxygen in the ocean
Answer: b) Excessive carbon dioxide in the atmosphere

What is a primary consumer in an ecosystem?
a) Grass
b) Herbivore
c) Decomposer
d) Carnivore
Answer: b) Herbivore

Which of the following is an example of a renewable resource?
a) Oil
b) Coal
c) Wind energy
d) Natural gas
Answer: c) Wind energy

What is the main cause of desertification?
a) Urbanization
b) Overgrazing
c) Afforestation
d) Crop rotation
Answer: b) Overgrazing

What term describes the variety of species in a particular area?
a) Habitat
b) Ecosystem
c) Biodiversity
d) Climate
Answer: c) Biodiversity

Which of the following is NOT a characteristic of the tundra biome?
a) Cold temperatures
b) Low precipitation
c) High biodiversity
d) Permafrost
Answer: c) High biodiversity

Which of the following processes involves the transformation of nitrogen in the atmosphere into compounds that plants can use?
a) Nitrogen fixation
b) Nitrification
c) Denitrification
d) Eutrophication
Answer: a) Nitrogen fixation

The concept of ecological footprint is used to measure:
a) The biodiversity of an ecosystem
b) The amount of resources consumed by humans
c) The size of a habitat for a species
d) The speed of ecological succession
Answer: b) The amount of resources consumed by humans

Which of the following is a direct result of deforestation?
a) Increased carbon dioxide absorption
b) Decreased biodiversity
c) Increased rainfall
d) Soil fertility improvement
Answer: b) Decreased biodiversity

Which gas is primarily responsible for the greenhouse effect?
a) Nitrogen
b) Oxygen
c) Carbon dioxide
d) Argon
Answer: c) Carbon dioxide

What is an example of an in-situ conservation method?
a) Seed bank
b) Botanical garden
c) National park
d) Zoological park
Answer: c) National park

Which of the following is an abiotic factor in an ecosystem?
a) Animals
b) Plants
c) Water
d) Bacteria
Answer: c) Water

Which biome is characterized by coniferous forests and cold winters?
a) Tropical rainforest
b) Savanna
c) Temperate forest
d) Taiga
Answer: d) Taiga

Which of the following is NOT a consequence of climate change?
a) Rising sea levels
b) Increased frequency of extreme weather events
c) More plant species diversity
d) Melting glaciers
Answer: c) More plant species diversity

The process by which plants release water vapor through small pores in their leaves is known as:
a) Evaporation
b) Precipitation
c) Transpiration
d) Infiltration
Answer: c) Transpiration

Which of the following is a non-renewable resource?
a) Wind
b) Solar energy
c) Coal
d) Geothermal energy
Answer: c) Coal

What term describes the role of an organism in its environment, including its interactions with other organisms?
a) Habitat
b) Niche
c) Community
d) Ecosystem
Answer: b) Niche

Which of the following is a major cause of the decline in amphibian populations worldwide?
a) Overfishing
b) Habitat loss
c) Excessive rainfall
d) Increased biodiversity
Answer: b) Habitat loss

Which of the following is NOT a method of sustainable resource management?
a) Afforestation
b) Overfishing
c) Renewable energy use
d) Crop rotation
Answer: b) Overfishing

Which of the following is a characteristic of a climax community?
a) It is always undergoing change
b) It is the final, stable stage of ecological succession
c) It contains mostly pioneer species
d) It has low biodiversity
Answer: b) It is the final, stable stage of ecological succession

Which of the following is a major environmental issue caused by industrialization?
a) Soil erosion
b) Deforestation
c) Air pollution
d) Biodiversity conservation
Answer: c) Air pollution