Q.What do you mean by Biodiversity? Describe its different methods of conservation in detail. OR Describe the structure of human sperm and ovum with diagrams.

Biodiversity is the variety of life at genetic, species and ecosystem levels; it is conserved by in-situ methods (protecting habitats — parks, sanctuaries, biosphere reserves) and ex-situ methods (zoos, gene banks, botanical gardens).

(This is a 5-mark essay with an OR alternative on sperm & ovum structure; the essay below answers the main question on Biodiversity and its conservation.)

What is biodiversity: The term biodiversity (coined by Edward Wilson) means the variety and variability among living organisms and the ecosystems they form. It is described at three levels:

1. Genetic diversity — variation of genes within a species (e.g. different varieties of rice, or Rauwolfia producing different amounts of reserpine).
2. Species diversity — variety of species in a region (e.g. more species in the Western Ghats than the Eastern Ghats).
3. Ecological / ecosystem diversity — variety of ecosystems / habitats (deserts, rainforests, wetlands, mangroves).

Methods of conservation: Conservation is broadly of two types —

A. In-situ conservation (on-site — in the natural habitat):

• Protecting organisms in their own natural surroundings, conserving the whole ecosystem.
• Includes: National Parks (e.g. Jim Corbett), Wildlife Sanctuaries, Biosphere Reserves (e.g. Nilgiri), Sacred groves (forest patches protected by local communities), and Biodiversity hotspots.
• Advantage: organisms remain in their natural habitat and continue to evolve.

B. Ex-situ conservation (off-site — outside the natural habitat):

• Protecting threatened species outside their natural home under human care. …