Our Environment – CBSE Class 10
1. An ecosystem includes
A) Living organisms and their physical environment
B) Only plants
C) Only animals
D) Only non-living things
Answer: Living organisms and their physical environment
2. Biotic components of ecosystem are
A) Living organisms
B) Sunlight
C) Water
D) Soil
Answer: Living organisms
3. Abiotic components of ecosystem are
A) Non-living things like sunlight, water, soil
B) Plants
C) Animals
D) Microorganisms
Answer: Non-living things like sunlight, water, soil
4. Producers in an ecosystem are
A) Green plants
B) Herbivores
C) Carnivores
D) Decomposers
Answer: Green plants
5. Consumers are
A) Organisms that eat other organisms for energy
B) Green plants
C) Decomposers
D) None
Answer: Organisms that eat other organisms for energy
6. Decomposers are
A) Organisms that break down dead matter
B) Herbivores
C) Carnivores
D) Plants
Answer: Organisms that break down dead matter
7. The flow of energy in ecosystem is
A) One-way from producers to consumers
B) Cyclic
C) Random
D) Absent
Answer: One-way from producers to consumers
8. Food chain shows
A) Sequence of organisms eating each other
B) Energy loss
C) Only plants
D) Only decomposers
Answer: Sequence of organisms eating each other
9. Food web represents
A) Interconnected food chains
B) Single chain
C) Decomposers only
D) Plants only
Answer: Interconnected food chains
10. Environmental problems include
A) Pollution, deforestation, global warming
B) Photosynthesis
C) Recycling
D) Planting trees
Answer: Pollution, deforestation, global warming
11. Air pollution is caused by
A) Smoke, exhaust gases, dust
B) Rain
C) Wind
D) Sunlight
Answer: Smoke, exhaust gases, dust
12. Water pollution is caused by
A) Industrial effluents and sewage
B) Sunlight
C) Photosynthesis
D) Wind
Answer: Industrial effluents and sewage
Our Environment – CBSE Class 10
13. Soil pollution is caused by
A) Pesticides, fertilizers, chemicals
B) Oxygen
C) Rain
D) Wind
Answer: Pesticides, fertilizers, chemicals
14. Noise pollution is caused by
A) Traffic, industries, loudspeakers
B) Water
C) Trees
D) Soil
Answer: Traffic, industries, loudspeakers
15. Ozone layer is present in
A) Stratosphere
B) Troposphere
C) Mesosphere
D) Ionosphere
Answer: Stratosphere
16. Ozone layer protects us from
A) Harmful ultraviolet radiation
B) Infrared rays
C) Gamma rays
D) Sound waves
Answer: Harmful ultraviolet radiation
17. CFCs deplete ozone because
A) They release chlorine atoms in stratosphere
B) They absorb sunlight
C) They pollute water
D) They are biodegradable
Answer: They release chlorine atoms in stratosphere
18. Global warming is caused by
A) Greenhouse gas accumulation
B) Rain
C) Photosynthesis
D) Recycling
Answer: Greenhouse gas accumulation
19. Greenhouse gases include
A) CO₂, CH₄, N₂O
B) Oxygen and nitrogen
C) Water only
D) Argon and helium
Answer: CO₂, CH₄, N₂O
20. Acid rain is caused by
A) Sulfur dioxide and nitrogen oxides in atmosphere
B) Carbon dioxide
C) Methane
D) Oxygen
Answer: Sulfur dioxide and nitrogen oxides in atmosphere
21. Waste is classified as
A) Biodegradable and non-biodegradable
B) Liquid and gas only
C) Solid only
D) None
Answer: Biodegradable and non-biodegradable
22. Biodegradable substances include
A) Food waste, paper, leaves
B) Plastics, metals
C) Glass
D) Electronic waste
Answer: Food waste, paper, leaves
23. Non-biodegradable substances include
A) Plastic, glass, metals
B) Leaves, vegetables
C) Food waste
D) Wood
Answer: Plastic, glass, metals
24. Biodegradable waste can be disposed by
A) Composting
B) Burning
C) Dumping in water
D) Burying in soil
Answer: Composting
25. Non-biodegradable waste can be reduced by
A) Recycling and reusing
B) Composting
C) Dumping in soil
D) Burning only
Answer: Recycling and reusing
Our Environment – CBSE Class 10
26. Eutrophication of water bodies is caused by
A) Excess fertilizers containing phosphates and nitrates
B) Acid rain
C) Plastic waste
D) Oil spills
Answer: Excess fertilizers containing phosphates and nitrates
27. Landfills are used for
A) Safe disposal of solid waste
B) Water purification
C) Generating electricity
D) Recycling
Answer: Safe disposal of solid waste
28. Biogas is produced from
A) Biodegradable waste by anaerobic digestion
B) Plastic waste
C) Metals
D) Glass
Answer: Biodegradable waste by anaerobic digestion
29. Major sources of air pollution include
A) Factories and vehicles
B) Trees and plants
C) Rain
D) Oceans
Answer: Factories and vehicles
30. Noise pollution affects
A) Hearing and mental health
B) Water quality
C) Soil fertility
D) Plant growth
Answer: Hearing and mental health
31. Global warming leads to
A) Melting of ice caps and rising sea levels
B) Increased rainfall only
C) Reduced sunlight
D) None
Answer: Melting of ice caps and rising sea levels
32. Ozone depletion causes
A) Skin cancer and eye cataract
B) Air pollution
C) Water pollution
D) Noise pollution
Answer: Skin cancer and eye cataract
33. CFCs are found in
A) Refrigerators, air conditioners, spray cans
B) Water
C) Soil
D) Vegetables
Answer: Refrigerators, air conditioners, spray cans
34. Solid waste management involves
A) Collection, segregation, recycling, and disposal
B) Only dumping
C) Only burning
D) Composting only
Answer: Collection, segregation, recycling, and disposal
35. Rainwater harvesting helps in
A) Conserving water and reducing runoff
B) Polluting soil
C) Increasing air pollution
D) None
Answer: Conserving water and reducing runoff
36. Non-biodegradable plastics cause
A) Soil and water pollution
B) Fertile soil
C) Clean environment
D) Composting
Answer: Soil and water pollution
37. Burning fossil fuels releases
A) Carbon dioxide and sulfur dioxide
B) Oxygen
C) Nitrogen
D) Water only
Answer: Carbon dioxide and sulfur dioxide
38. Waste segregation involves
A) Separating biodegradable from non-biodegradable waste
B) Mixing all waste
C) Only dumping in landfills
D) Burning all waste
Answer: Separating biodegradable from non-biodegradable waste
39. Plastic pollution can be reduced by
A) Reuse, recycle, use alternatives
B) Burning in open
C) Dumping in rivers
D) None
Answer: Reuse, recycle, use alternatives
Our Environment – CBSE Class 10
40. Biodegradable substances are decomposed by
A) Microorganisms
B) Sunlight only
C) Heat only
D) Wind
Answer: Microorganisms
41. Excess use of fertilizers leads to
A) Water pollution
B) Air purification
C) Soil enrichment only
D) None
Answer: Water pollution
42. Land pollution is caused by
A) Industrial waste, plastics, chemicals
B) Water
C) Sunlight
D) Air
Answer: Industrial waste, plastics, chemicals
43. Compost is
A) Nutrient-rich manure from biodegradable waste
B) Plastic waste
C) Chemical fertilizer
D) Metal waste
Answer: Nutrient-rich manure from biodegradable waste
44. Waste management helps to
A) Protect environment and health
B) Increase pollution
C) Reduce soil fertility
D) None
Answer: Protect environment and health
45. Ozone hole is largest over
A) Antarctica
B) Arctic
C) Tropics
D) Equator
Answer: Antarctica
46. Greenhouse effect is caused by
A) CO₂, CH₄, N₂O trapping heat
B) Ozone layer
C) Rainfall
D) Soil
Answer: CO₂, CH₄, N₂O trapping heat
47. Reforestation helps in
A) Reducing CO₂ and controlling global warming
B) Increasing pollution
C) Soil degradation
D) None
Answer: Reducing CO₂ and controlling global warming
48. Industrial waste can be treated by
A) Effluent treatment plants
B) Dumping in rivers
C) Burning only
D) None
Answer: Effluent treatment plants
49. Non-biodegradable waste remains in environment for
A) Very long time
B) Short time
C) Days only
D) Weeks only
Answer: Very long time
50. Environmental protection can be done by
A) Reducing, Reusing, Recycling (3R)
B) Increasing pollution
C) Dumping waste in rivers
D) None
Answer: Reducing, Reusing, Recycling (3R)