Environment, Ecology & Biodiversity MCQs for Competitive Exams

India General Knowledge

MODULE 9: Environment, Ecology & Biodiversity MCQs

Topic: Environment, Ecology & Biodiversity MCQs for Competitive Exams

The questions are systematically divided into clearly defined sub-topics and arranged in a logical and conceptual sequence, ensuring clarity, syllabus alignment, and high relevance for UPSC, State PSCs, SSC, Banking, Railways, Forest Services, Teaching Eligibility Tests, University & Entrance Examinations.

Sub-Topic 1: Basics of Environment & Ecology

Q1. Environment includes:

A. Only living organisms
B. Only non-living components
C. Living and non-living components
D. Only climatic factors

Correct Answer: C

Explanation:
The environment comprises biotic (living) components like plants and animals and abiotic (non-living) components such as air, water, soil, and climate.

Q2. Ecology is the study of:

A. Earth’s physical features
B. Human society
C. Interaction between organisms and environment
D. Atmospheric layers

Correct Answer: C

Explanation:
Ecology examines relationships among organisms and their interaction with the surrounding environment.

Q3. The smallest unit of ecological study is:

A. Population
B. Community
C. Ecosystem
D. Individual organism

Correct Answer: D

Explanation:
An individual organism is the basic unit, from which higher levels like population and ecosystem are built.

Sub-Topic 2: Ecosystem – Structure & Function

Q4. An ecosystem is formed by:

A. Only plants
B. Only animals
C. Living organisms and physical environment
D. Only microorganisms

Correct Answer: C

Explanation:
An ecosystem involves interaction between biotic and abiotic components, functioning as a unit.

Q5. Producers in an ecosystem are generally:

A. Animals
B. Green plants
C. Decomposers
D. Parasites

Correct Answer: B

Explanation:
Green plants act as producers by making food through photosynthesis.

Q6. Which organisms break down dead organic matter?

A. Herbivores
B. Carnivores
C. Producers
D. Decomposers

Correct Answer: D

Explanation:
Decomposers recycle nutrients by breaking down dead plants and animals.

Sub-Topic 3: Food Chain, Food Web & Energy Flow

Q7. Energy flow in an ecosystem is:

A. Cyclic
B. Random
C. Unidirectional
D. Bidirectional

Correct Answer: C

Explanation:
Energy flows from producers to consumers and is not recycled back.

Q8. A food web represents:

A. Single feeding relationship
B. Multiple interconnected food chains
C. Energy loss only
D. Decomposer dominance

Correct Answer: B

Explanation:
Food webs show complex feeding relationships, increasing ecosystem stability.

Q9. According to Lindeman’s 10% law:

A. 10% energy is lost
B. 10% energy is transferred to next trophic level
C. 90% energy is transferred
D. Energy transfer is equal

Correct Answer: B

Explanation:
Only about 10% of energy passes to the next trophic level.

Sub-Topic 4: Biogeochemical Cycles

Q10. The movement of nutrients between living and non-living components is called:

A. Energy flow
B. Biogeochemical cycle
C. Food chain
D. Ecological succession

Correct Answer: B

Explanation:
Biogeochemical cycles ensure continuous circulation of essential elements.

Q11. Which cycle has no significant gaseous phase?

A. Carbon cycle
B. Nitrogen cycle
C. Phosphorus cycle
D. Oxygen cycle

Correct Answer: C

Explanation:
The phosphorus cycle mainly occurs through rocks, soil, and water.

Q12. Nitrogen fixation converts nitrogen into:

A. Carbon dioxide
B. Ammonia
C. Oxygen
D. Methane

Correct Answer: B

Explanation:
Nitrogen-fixing bacteria convert nitrogen into ammonia, usable by plants.

Sub-Topic 5: Biodiversity Concepts

Q13. Biodiversity refers to:

A. Species diversity only
B. Genetic diversity only
C. Ecosystem diversity only
D. Genetic, species, and ecosystem diversity

Correct Answer: D

Explanation:
Biodiversity includes diversity at all three levels.

Q14. India is a megadiverse country because of:

A. Large population
B. Vast deserts
C. High species richness and endemism
D. Long coastline

Correct Answer: C

Explanation:
India supports rich flora and fauna across varied ecosystems.

Q15. Species found only in a particular region are called:

A. Exotic species
B. Endemic species
C. Keystone species
D. Indicator species

Correct Answer: B

Explanation:
Endemic species are restricted to specific geographic regions.

Sub-Topic 6: Biodiversity Conservation

Q16. Conservation of species in their natural habitat is known as:

A. Ex-situ conservation
B. In-situ conservation
C. Artificial conservation
D. Captive breeding

Correct Answer: B

Explanation:
In-situ conservation protects species within their natural ecosystems.

Q17. Which is an example of ex-situ conservation?

A. National parks
B. Wildlife sanctuaries
C. Zoological parks
D. Biosphere reserves

Correct Answer: C

Explanation:
Ex-situ conservation occurs outside natural habitats, like zoos and botanical gardens.

Q18. Biodiversity hotspots are regions with:

A. Low species diversity
B. High endemism and threat levels
C. Only forest ecosystems
D. Only marine ecosystems

Correct Answer: B

Explanation:
Hotspots are areas with exceptionally high biodiversity under threat.

Sub-Topic 7: Environmental Pollution

Q19. Eutrophication mainly affects:

A. Air
B. Soil
C. Water bodies
D. Noise levels

Correct Answer: C

Explanation:
Eutrophication causes excessive nutrient enrichment in water bodies.

Q20. Acid rain is caused by emissions of:

A. Carbon monoxide
B. Sulphur dioxide and nitrogen oxides
C. Methane
D. Ozone

Correct Answer: B

Explanation:
These gases react with moisture to form acidic precipitation.

Q21. Major source of urban air pollution in India is:

A. Agriculture
B. Volcanic activity
C. Vehicular emissions
D. Forest cover

Correct Answer: C

Explanation:
Rapid urbanization and traffic make vehicular emissions the main source.

Sub-Topic 8: Climate Change & Global Warming

Q22. Global warming refers to:

A. Cooling of Earth
B. Natural climate variability
C. Rise in average global temperature
D. Seasonal change

Correct Answer: C

Explanation:
Global warming is caused by increased greenhouse gas concentration.

Q23. The most abundant greenhouse gas emitted by human activities is:

A. Methane
B. Nitrous oxide
C. Carbon dioxide
D. Ozone

Correct Answer: C

Explanation:
Carbon dioxide is emitted in large quantities from fossil fuel burning.

Q24. Climate change in India is most evident through:

A. Reduced monsoon variability
B. Extreme weather events
C. Decreased temperature
D. Stable ecosystems

Correct Answer: B

Explanation:
India experiences floods, droughts, cyclones, and heatwaves.

Sub-Topic 9: Sustainable Development

Q25. Sustainable development aims to:

A. Maximize industrial output
B. Conserve environment only
C. Balance development and environmental protection
D. Restrict economic growth

Correct Answer: C

Explanation:
It integrates economic, social, and environmental objectives.

Q26. The concept of sustainable development was defined in:

A. Stockholm Declaration
B. Brundtland Report
C. Rio Declaration
D. Paris Agreement

Correct Answer: B

Explanation:
The Brundtland Report (1987) provided the standard definition.

Q27. Which SDG deals directly with climate action?

A. SDG 11
B. SDG 12
C. SDG 13
D. SDG 15

Correct Answer: C

Explanation:
SDG 13 focuses on combating climate change.

Sub-Topic 10: Integrated Perspective for Competitive Exams

Q28. Loss of biodiversity leads to:

A. Increased ecosystem stability
B. Reduced ecosystem resilience
C. Higher productivity
D. Better nutrient cycling

Correct Answer: B

Explanation:
Biodiversity loss weakens ecosystem functioning and stability.

Q29. Ecological balance means:

A. Absence of humans
B. Equal species population
C. Stable interaction among ecosystem components
D. Maximum energy flow

Correct Answer: C

Explanation:
Balanced interactions ensure ecosystem sustainability.

Q30. Environment, ecology, and biodiversity are important for competitive exams because:

A. They are purely theoretical
B. They link science with current affairs and policy
C. They are optional topics
D. They are rarely asked

Correct Answer: B

Explanation:
These topics integrate static concepts with dynamic current issues, making them highly exam-relevant.

• Environment ecology biodiversity MCQs

• Environment GK MCQs for competitive exams

• Ecology and ecosystem MCQs

• Biodiversity conservation MCQs

• Climate change environment MCQs

• Sustainable development MCQs

• UPSC environment ecology questions

• State PSC environment MCQs

⭐ Why Environment, Ecology & Biodiversity MCQs Are Essential for Competitive Exams

Environment, Ecology, and Biodiversity form a high-scoring and concept-driven section of the General Studies syllabus. Questions from this area are regularly asked in UPSC, State PSCs, SSC, Banking, Railways, Forest Services, and Teaching Eligibility Tests, often linked with current environmental issues.

This MCQ set helps aspirants:

• Build strong fundamentals of environment, ecology, and biodiversity

• Understand ecosystem processes, conservation, and climate change

• Link static concepts with exam-oriented application

• Improve accuracy and confidence in objective-type examinations

Regular practice of these MCQs ensures conceptual clarity and exam readiness.

❓ FAQ Section

Q1. Are Environment, Ecology & Biodiversity important for UPSC and State PSC exams?

Yes. These topics are core areas of General Studies and appear frequently in both Prelims and Mains.

Q2. What type of environment questions are asked in competitive exams?

Exams usually ask concept-based MCQs on ecosystems, biodiversity conservation, pollution, climate change, and sustainability.

Q3. Are these MCQs useful for SSC, Banking, and Railway exams?

Yes. SSC, Banking, and Railway exams regularly include environment and ecology questions in General Awareness sections.

Q4. Is prior science background required to study environment MCQs?

No. The topic can be prepared easily with basic concepts and regular MCQ practice.

Q5. How can aspirants score well in Environment & Ecology?

By understanding fundamentals, revising key terms, and practicing exam-oriented MCQs with explanations.

🎯 Targeted Competitive & Academic Examinations

These Environment, Ecology & Biodiversity MCQs are designed for:

• UPSC Civil Services Examination (Prelims & Mains)

• State Public Service Commissions (APSC, BPSC, UPPSC, RPSC, MPPSC, etc.)

• SSC Exams (CGL, CHSL, MTS, GD)

• Banking Exams (IBPS, SBI, RBI, NABARD)

• Railway Exams (RRB NTPC, Group D)

• Forest Services & Environmental Exams

• Teaching Eligibility Tests (CTET & State TETs)

• University, College & Entrance Examinations

• School-level Competitive & Board Examinations