✅ Q1. Which of the following groups contain only biodegradable items?
🎯 (a) Grass, flowers and leather
✅ Q2. Which of the following constitute a food chain?
🎯 (b) Grass, goat and human
✅ Q3. Which of the following are environment-friendly practices?
🎯 (d) All of the above
✔ Carrying cloth-bags while shopping
✔ Switching off unnecessary lights and fans
✔ Walking to school instead of using vehicles
✅ Q4. What will happen if we kill all the organisms in one trophic level?
🎯 The entire food chain will collapse:
- Organisms at the next trophic level will starve and decrease in number.
- Organisms at the previous level may grow excessively, disturbing the ecosystem balance.
✅ Q5. Will the impact of removing all the organisms in a trophic level be different for different trophic levels? Can the organisms of any trophic level be removed without causing any damage to the ecosystem?
🎯 Yes, the impact will be different at each level because:
- Removing producers eliminates food for all consumers.
- Removing top predators can cause overpopulation of lower levels.
🎯 No trophic level can be removed without causing damage, as all levels are interconnected.
✅ Q6. What is biological magnification? Will the levels of this magnification be different at different levels of the ecosystem?
🎯 Biological magnification refers to the increase in concentration of harmful chemicals (like pesticides) in organisms at higher trophic levels of a food chain.
🎯 Yes, it is higher at the top of the food chain because chemicals accumulate in bodies over time and get concentrated as they move up the chain.
✅ Q7. What are the problems caused by the non-biodegradable wastes that we generate?
🎯 Problems include:
- Pollution of soil, water, and air.
- Harm to wildlife and marine life.
- Blocking of drains and rivers.
- Long-term damage to ecosystems as these materials persist for years.
✅ Q8. If all the waste we generate is biodegradable, will this have no impact on the environment?
🎯 Even biodegradable waste can harm the environment if produced in excess:
- Overloads decomposers.
- Can produce foul smell, methane gas.
- Can contaminate water and reduce soil fertility if unmanaged.
✅ Q9. Why is damage to the ozone layer a cause for concern? What steps are being taken to limit this damage?
🎯 The ozone layer protects us from harmful UV rays that can cause skin cancer, cataracts, and harm plants and animals.
🎯 Steps to protect ozone:
- Banning of ozone-depleting substances (like CFCs) through agreements like the Montreal Protocol.
- Encouraging use of eco-friendly products and technologies.