Question

‘Biological magnification’ is the phenomenon of ______.

Options

• increase in concentration of pesticides (chlorinated hydrocarbons) at successive trophic levels

• increase in concentration of sewage in water

• increase in biological activity of micro-organisms

• biodegradation of sewage waste

Answer 1

‘Biological magnification’ is the phenomenon of increase in concentration of pesticides (chlorinated hydrocarbons) at successive trophic levels.

Explanation:

Biological magnification (biomagnification) refers to the increasing concentration of toxic substances like pesticides as they move up the food chain from lower to higher trophic levels. These substances, such as DDT, accumulate in organisms because they cannot be metabolized or excreted easily. As a result, organisms at higher trophic levels, such as predatory birds or fish-eating animals, have much higher concentrations of these toxins than those at lower levels. This magnification causes severe ecological and health problems in top-level consumers.