Question

The increasing concentration of a substance, such as a toxic chemical, in the tissues of tolerant organisms at successively higher levels in a food chain, is known as biological magnification. Enter 1 for True and 2 for False.

Answer 1

The toxic substances and a large number of pesticides are non- biodegradable. Therefore, the concentration of the toxic materials increases at each trophic level of a food chain. This phenomenon is called biomagnification, or biological concentration. River water may have a very low concentration of DDT, but the carnivorous fish in that river may contain a high concentration of DDT and be unfit for eating by man or birds.