What is an ecosystem?

An ecosystem is a community of living organisms interacting with their physical environment, exchanging energy and nutrients.

What are the major types of pollution?

Major types of pollution include air, water, soil, noise, and thermal pollution affecting human health and environment.

How can we conserve biodiversity?

Conservation of biodiversity includes protecting habitats, reducing pollution, afforestation, and promoting sustainable development.

1. What is the environment?

The environment includes all living (biotic) and non-living (abiotic) factors interacting together — such as plants, animals, soil, water, air, temperature and sunlight.

2. What is an ecosystem and its main components?

An ecosystem consists of organisms (producers, consumers, decomposers) interacting with each other and with physical environment (soil, water, atmosphere), exchanging energy and cycling nutrients.

4. What is a food chain and a food web?

A food chain shows a linear sequence of who eats whom (e.g., grass → grasshopper → frog → snake). Food webs connect multiple chains showing complex feeding relationships in an ecosystem.

5. How does energy flow through an ecosystem?

Energy flows from producers to consumers; at each trophic level most energy is lost as heat and only a small fraction (~10%) is passed to the next level. This leads to pyramid-shaped energy distributions.

6. What maintains a balanced ecosystem and what disrupts it?

Balance is maintained by interactions among species and physical factors. Disruptions include habitat loss, pollution, over-exploitation, introduction of invasive species and climate change leading to loss of species and ecosystem services.

7. What is biodiversity and why is it important?

Biodiversity refers to variety at genetic, species and ecosystem levels. It provides ecosystem services: food, medicines, clean water, pollination and resilience to environmental change.

8. What causes habitat loss and what are its effects?

Habitat loss from deforestation, urbanisation, agriculture and infrastructure leads to species decline, reduced genetic diversity and ecosystem instability. Fragmentation isolates populations and increases extinction risk.

9. What are invasive species and give an example?

Invasive species are non-native organisms that outcompete locals, altering ecosystems. Example: water hyacinth rapidly covers water bodies blocking sunlight and oxygen, harming aquatic life. Control includes mechanical removal and biological agents.

16. What are greenhouse gases and how do they affect climate?

Greenhouse gases (CO₂, CH₄, N₂O) trap outgoing infrared radiation, warming the planet — known as the greenhouse effect. Increased concentrations lead to global warming and climate change.

Our Environment | Class 10 Science Notes

📘 Introduction

This chapter explains Our Environment, covering ecosystems, biodiversity, pollution, conservation, and sustainable development. Essential for NEET, SSC, Railway, and Police Bharti exams and Class 10 board preparation.

🔹 Key Concepts

Ecosystem: Interaction of living organisms with environment.
Biodiversity: Variety of species in an ecosystem.
Pollution: Contamination of air, water, soil, or noise.
Conservation: Protection of natural resources and biodiversity.
Sustainable Development: Using resources without harming future generations.

📊 Chapter Summary Table

Concept	Definition / Explanation	Importance
Ecosystem	Community of organisms & environment interactions	Maintains ecological balance
Biodiversity	Variety of species in an area	Supports ecosystem stability
Pollution	Air, water, soil, noise contamination	Harmful to health & environment
Conservation	Protection of resources & biodiversity	Ensures sustainable use
Sustainable Development	Using resources responsibly	Balances needs of present & future

🧮 Practice Questions

What is an ecosystem? ➡ Show Answer
An ecosystem is a community of living organisms interacting with their physical environment.
List major types of pollution. ➡ Show Answer
Air, water, soil, noise, and thermal pollution.
How can biodiversity be conserved? ➡ Show Answer
By protecting habitats, reducing pollution, afforestation, and promoting sustainable development.

Ecosystem Biodiversity Pollution Conservation

NCERT Class 10 — Our Environment

10. What causes air pollution and what are its effects?

11. What are the sources and effects of water pollution?

12. What causes soil erosion and how can it be controlled?

📘 Introduction

🔹 Key Concepts

📊 Chapter Summary Table

🧮 Practice Questions

1. What is the environment?

2. What is an ecosystem and its main components?

3. Who are producers, consumers and decomposers? Give examples.

4. What is a food chain and a food web?

5. How does energy flow through an ecosystem?

6. What maintains a balanced ecosystem and what disrupts it?

7. What is biodiversity and why is it important?

8. What causes habitat loss and what are its effects?

9. What are invasive species and give an example?

10. What causes air pollution and what are its effects?

11. What are the sources and effects of water pollution?

12. What causes soil erosion and how can it be controlled?

13. What are types of solid waste and basic disposal methods?

14. What is biodegradation and how is composting useful?

15. What is the ozone layer and why is it important?

16. What are greenhouse gases and how do they affect climate?

17. What is global warming and what are its impacts?

18. What is acid rain and how does it form?

19. What is sustainable development?

20. How can biodiversity be conserved?

21. How has international action addressed ozone depletion?

22. What is rainwater harvesting and why is it useful?

23. What is afforestation and how does it help the environment?

24. What causes environmental degradation?

25. What are sustainable agriculture practices?

26. What role do mangroves play in coastal ecosystems?

27. Why are coral reefs important and what threatens them?

28. What is e-waste and why is proper disposal important?

29. How can public awareness help protect the environment?

30. What role does government policy play in environmental protection?

31. How do NGOs and community groups contribute to environmental protection?

32. Why are wetlands important?

33. What constitutes sustainable transport?

34. How does recycling help the environment?

35. How can urban planning improve environmental health?

36. What is Environmental Impact Assessment (EIA)?

37. What is sustainable natural resource management?

38. What is carrying capacity?

39. What are biogeochemical cycles and why are they important?

40. Why are pollinators important and what threatens them?

41. What is community-based conservation?

42. What are green belts and their benefits?

43. What is environmental ethics?

44. Why is environmental monitoring necessary?

45. What is the difference between climate mitigation and adaptation?

46. What is sustainable tourism?

47. Give examples of green technologies.

48. What is ocean acidification and why is it a concern?

49. What is environmental stewardship and what can individuals do?

50. Final summary: Our Environment — key takeaways