1. Food Chain vs Food Web:
Food Chain: Single linear pathway of energy flow. Simple, less stable.
Food Web: Multiple interconnected chains. Complex, more stable (alternate food sources).
2. Producers vs Consumers:
Producers: Make their own food via photosynthesis. Examples: Plants, algae.
Consumers: Depend on other organisms for food. Examples: Herbivores, carnivores.
3. Biodegradable vs Non-Biodegradable:
Biodegradable: Decompose naturally (days to months). Safe for environment.
Non-Biodegradable: Don't decompose (persist for centuries). Cause pollution, biomagnification.
4. Why are food chains usually short (3-4 levels)? At each
level, 90% energy is lost. After 4-5 transfers, very little energy remains to support another level.
5. Why do we need decomposers? Without decomposers, dead
matter would accumulate. Nutrients would be locked up, not recycled. Producers would eventually run out of
nutrients.
6. Why shouldn't we burn plastic? Burning plastic releases
toxic gases (dioxins, furans) that cause cancer and respiratory diseases. Better to recycle or dispose
properly.
7. Why is there more DDT in eagles than in fish?
Biomagnification. DDT is fat-soluble, not excreted. Small fish accumulate low DDT. Eagle eats many fish, DDT
concentrations add up.
8. How can you reduce your carbon footprint? Use public
transport, reduce electricity use, eat local food, plant trees, use renewable energy, recycle.
9. Why is Montreal Protocol important? It banned production
of CFCs and other ozone-depleting substances. Has led to gradual recovery of the ozone layer.
10. Pyramid of Energy: Always upright because energy
decreases at each level (10% law). Unlike pyramid of numbers or biomass, which can be inverted.
