1. The term “ecosystem” was first coined by:
A) Charles Darwin
B) Ernst Haeckel
C) A.G. Tansley
D) Lamarck
Answer: C) A.G. Tansley
2. The largest ecosystem on Earth is:
A) Forest
B) Ocean
C) Desert
D) Grassland
Answer: B) Ocean
3. Organisms that prepare their own food are called:
A) Consumers
B) Decomposers
C) Producers
D) Parasites
Answer: C) Producers
4. The study of interactions between organisms and their environment is called:
A) Biology
B) Ecology
C) Zoology
D) Botany
Answer: B) Ecology
5. Which of the following is a biotic component?
A) Water
B) Soil
C) Temperature
D) Plants
Answer: D) Plants
6. Energy enters the ecosystem through:
A) Decomposers
B) Carnivores
C) Producers
D) Omnivores
Answer: C) Producers
7. The process by which plants lose water vapor is called:
A) Respiration
B) Photosynthesis
C) Transpiration
D) Evaporation
Answer: C) Transpiration
8. The ozone layer protects us from:
A) Infrared rays
B) X-rays
C) Ultraviolet rays
D) Gamma rays
Answer: C) Ultraviolet rays
9. A food chain always begins with:
A) Consumers
B) Decomposers
C) Producers
D) Carnivores
Answer: C) Producers
10. Animals that eat both plants and animals are called:
A) Herbivores
B) Carnivores
C) Omnivores
D) Scavengers
Answer: C) Omnivores
11. Which gas is mainly responsible for global warming?
A) Oxygen
B) Nitrogen
C) Carbon dioxide
D) Hydrogen
Answer: C) Carbon dioxide
12. The natural home of an organism is called its:
A) Niche
B) Habitat
C) Biome
D) Community
Answer: B) Habitat
13. The cycling of water between earth and atmosphere is called:
A) Nitrogen cycle
B) Carbon cycle
C) Water cycle
D) Oxygen cycle
Answer: C) Water cycle
14. Which of the following is a renewable resource?
A) Coal
B) Petroleum
C) Solar energy
D) Natural gas
Answer: C) Solar energy
15. Deforestation mainly leads to:
A) Soil conservation
B) Increase in rainfall
C) Soil erosion
D) More oxygen production
Answer: C) Soil erosion
16. The variety of living organisms in a region is called:
A) Ecosystem
B) Biodiversity
C) Population
D) Habitat
Answer: B) Biodiversity
17. Which layer of the atmosphere contains the ozone layer?
A) Troposphere
B) Stratosphere
C) Mesosphere
D) Thermosphere
Answer: B) Stratosphere
18. A group of organisms of the same species living in a particular area is called:
A) Community
B) Population
C) Ecosystem
D) Biome
Answer: B) Population
19. Lichens are an example of:
A) Parasitism
B) Mutualism
C) Commensalism
D) Predation
Answer: B) Mutualism
20. Which of the following is a non-biodegradable pollutant?
A) Paper
B) Vegetable waste
C) Plastic
D) Cotton
Answer: C) Plastic
21. The transfer of energy from one trophic level to another follows:
A) 100% rule
B) 50% rule
C) 10% rule
D) 90% rule
Answer: C) 10% rule
22. Which of the following causes acid rain?
A) Carbon dioxide
B) Methane
C) Sulfur dioxide
D) Oxygen
Answer: C) Sulfur dioxide
23. Desert plants are called:
A) Hydrophytes
B) Xerophytes
C) Mesophytes
D) Halophytes
Answer: B) Xerophytes
24. The gradual change in species composition in an area over time is called:
A) Evolution
B) Adaptation
C) Succession
D) Mutation
Answer: C) Succession
25. Which ecosystem has the highest biodiversity?
A) Desert
B) Tundra
C) Tropical rainforest
D) Grassland
Answer: C) Tropical rainforest
26. Excessive nutrients in water bodies cause:
A) Deforestation
B) Eutrophication
C) Desertification
D) Acid rain
Answer: B) Eutrophication
27. Which of the following is a secondary consumer?
A) Grass
B) Deer
C) Tiger
D) Algae
Answer: C) Tiger
28. The greenhouse effect helps in:
A) Cooling the Earth
B) Maintaining Earth’s temperature
C) Destroying ozone
D) Stopping rainfall
Answer: B) Maintaining Earth’s temperature
29. The main source of energy for Earth is:
A) Moon
B) Wind
C) Sun
D) Ocean
Answer: C) Sun
30. Which organization works globally for environmental protection?
A) WHO
B) UNESCO
C) UNEP
D) UNICEF
Answer: C) UNEP