KTUYSBeta
Log inSign up

Cheat sheet · Class 12 · CBSE · Science Biology

Biodiversity and Conservation cheat sheet

The whole chapter on one page: key formulas, facts and the points to remember, for quick revision before a test.

CBSE Class 12 · Biology

Cheat sheet

Chapter 13Biodiversity and Conservation

The Evil Quartet: habitat loss, over-exploitation, alien species, co-extinctions.

1. Levels of Biodiversity

  • Genetic (Rauwolfia varieties).
  • Species (Western Ghats amphibians).
  • Ecological (deserts, forests, wetlands).

India: 2.4% of land, ~8.1% of species; one of 12 mega-diverse countries.

2. Patterns

  • Diversity falls from equator to poles.
  • Species–area relation: log⁡S=log⁡C+Zlog⁡A\log S = \log C + Z\log A.
  • Rivet popper hypothesis (Ehrlich).

3. Loss (Evil Quartet)

  • habitat loss & fragmentation
  • over-exploitation
  • alien species invasion
  • co-extinctions

e.g. Nile perch in Lake Victoria; Parthenium, Lantana, water hyacinth.

4. Conservation

TypeExamples
In situbiodiversity hotspots, national parks, sanctuaries, biosphere reserves, sacred groves
Ex situzoos, botanical gardens, seed banks, cryopreservation

India has 3 hotspots in its regions: Western Ghats–Sri Lanka, Indo-Burma, Himalaya.

5. Key Points

  • Earth Summit, Rio 1992; WSSD Johannesburg 2002.
  • IUCN Red List.
  • Amazon: ‘lungs of the planet’.
  • Hotspots cover < 2% of land.

Remember: 3 levels | Evil Quartet | in situ vs ex situ

Biodiversity and Conservation: questions and notes

More Class 12 · CBSE · Science Biology cheat sheets

Practise Biodiversity and Conservation

Sign up free to practise the full chapter. Questions you get wrong come back until you've mastered them.

Start practising free

Free to start · No credit card needed