GK
BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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In an area where DDT had been used extensively, the population of birds declined significantly because
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Many of the birds eggs laid, did not hatch
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Earthworms in the area got eradicated
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Cobras were feeding exclusively on birds
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Birds stopped laying eggs
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Explanation:
Detailed explanation-1: -Higher amounts of DDT disturb calcium metabolism of birds resulting in thinning of egg shells and their premature breaking that kills the embryos. Thus many of the eggs laid by birds did not hatch.
Detailed explanation-2: -Biomagnification of DDT leads to an increase in its concentration at the higher trophic level and its higher concentration in birds leads to the disturbance in their calcium metabolism. This causes the premature breaking of eggs in birds due to thinning of eggshell.
There is 1 question to complete.