Question

Biomagnification of DDT causes decline in bird population by

• A. Brining disturbance in calcium metabolism
• B. Thinning of egg shell
• C. Premature breaking of eggs
• D. All of the above

Answer 1

The correct option is D All of the above

Dichlorodiphenyltrichloroethane or DDT is a crystalline, colourless and odourless compound which is used as an insecticide. DDT on runoff from the fields reach the water bodies and gets accumulated in the bodies of fishes. When fishes are eaten by birds, it gets accumulated in the body of birds and hence, in this way it enters the food chain. With each successive trophic level, concentration of DDT increases and this is known as biomagnification.

High concentration of DDT disturbs the calcium metabolism of birds and causes thinning of egg shells. and premature breaking. This leads to decline in their population.

Hence, all the options are correct.

So, the correct answer is 'All of the above'.