Question

What happens in biological magnification?

• A. A progressive increase in the level of energy transferred through trophic levels
• B. A progressive increase in the body weight through trophic levels
• C. A progressive increase in the number of organisms through trophic levels
• D. A progressive increase in the amount of harmful substances through trophic levels

Answer 1

The correct option is D A progressive increase in the amount of harmful substances through trophic levels

Biomagnification (or bioaccumulation) refers to the ability of living organisms to accumulate certain chemicals to a concentration larger than that occurring in their inorganic, non-living environment, or in the case of animals, in the food that they eat. The contaminants include heavy metals namely mercury, arsenic, pesticides such as DDT, and polychlorinated biphenyls (PCBs) compounds which are then taken up by organisms because of the food they consume or the intoxication of their environment. These materials are highly present in a variety of household and industrial chemicals. The harmful substances then build up inside the organism’s cells. When organisms in the higher food chain consume the organisms containing the toxins below their trophic levels, the toxins gradually become concentrated in the higher food chain. Because this is a repetitive process in the ecosystem and throughout the entire food chain, the higher organisms are the ones that will accumulate most of the toxins.

So the correct option is 'a progressive increase in the level of energy transferred through trophic levels'.