Answers

Abhimanyu
Aug 3, 2020

(i) Biomagnification can be defined as the increase in concentration of toxicants at successive trophic levels.
(ii) Toxic substances accumulated by organism cannot be metabolised or excreted. Therefore, they get accumulated in an organism and passes on to higher trophic levels.

The population of fish eating birds living on the bank of a contaminated lake gets affected adversely by DDT. Being highly poisonous, DDT disturbs the calcium  metabolism in birds which causes thinning of their egg shells and premature breaking of such eggs.
It leads to decline in the bird population.