Class 12th Biology 2014 Set3 Delhi Board Paper Solution
There are many animals that have become extinct in the wild but continue to be maintained in Zoological parks.
(i) What type of biodiversity conservation is observed in this case?
(ii) Explain any other two ways which help in this type of conservation.
(i) It is an example of ex-situ conservation (off-site conservation). In this approach, threatened plants and animals are taken out of their natural habitat and placed in to suitable settings and given special care.
(ii) Cryopreservation and tissue culture are two ways that help in ex-situ conservation.
In cryopreservation, gametes of threatened species are preserved in viable and fertile conditions at sub-zero temperatures, which help in preserving these cells for longer periods.
In tissue culture, plants are propagated from a small mass of tissue, called callus.
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