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Biodiversity and Conservation

NCERT Class 12 Biology Chapter 13

Biodiversity and Conservation for Class 12 Biology and NEET: levels and patterns of biodiversity, its loss, hotspots, and in situ and ex situ conservation.

3 topics Updated 8 Nov 2026

For: Class 12 and NEET, unless a topic says otherwise

In the syllabus: NEET Class 12 syllabus

With your textbook

NCERT Biology (Class 12), Chapter 13 “Biodiversity and Conservation”, reprint 2026-27.

Open the official NCERT chapter (PDF, 2.3 MB, ncert.nic.in)

Checked on 19 Oct 2026.

Learn in this order

  1. Biodiversity: levels, patterns and loss

    Biodiversity for Class 12 Biology and NEET: genetic, species and ecological diversity, species counts, latitude and species–area patterns, and loss.

    NCERT Section 13.1 21 min read 3 solved examples 10 practice questions

  2. Biodiversity conservation

    Biodiversity conservation for Class 12 Biology and NEET: utilitarian and ethical reasons, hotspots, protected areas, sacred groves and ex situ methods.

    NCERT Section 13.2 13 min read 3 solved examples 9 practice questions

  3. Red Data Book and the IUCN Red List

    The IUCN Red List, its threat categories (critically endangered, endangered, vulnerable) and India’s Red Data Books.

    NEET only 11 min read 3 solved examples 9 practice questions

Key formulas in this chapter

Biodiversity

  • levels: genetic, species, ecological
  • log S = log C + Z log A
  • S = C AZ
  • Z: 0.1–0.2 in a region; 0.6–1.2 continents
  • India: 2.4% of land, 8.1% of species
  • extinctions now 100–1000 times faster

Biodiversity conservation

  • arguments: narrowly, broadly utilitarian; ethical
  • in situ: on site; ex situ: off site
  • hotspots: 25 + 9 = 34; 3 in India
  • India: 14 BR, 90 NP, 448 sanctuaries
  • Earth Summit: Rio, 1992
  • WSSD: Johannesburg, 2002

Red Data Book

  • threatened: CR, EN and VU
  • risk: CR > EN > VU > NT > LC
  • also EX, EW; DD, NE
  • IUCN 2004: 784 extinctions in 500 years
  • 338 + 359 + 87 = 784

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