Question

(i) What is biological magnification ? 

(ii) If the concentration of DDT is 0.2 ppm in water of lake, what would be its likely concentration in fish in the food chain ?

 Plankton→ Fish → Fish eating birds.

Answer 1

(i) Biological Magnification: The increase in the concentration of a chemical per unit  weight of the organisms with the successive rise in tropic level. 

(ii) Water → Plankton → Fish → Fish eating bird

(0.2ppm.)    (S.0ppm)         (240ppm)

Concentration in Fish would be approximately 240 ppm.