Question

If a non-degradable and fat soluble pollutant, such as DDT enters the food chain, the pollutant

• A. magnifies in concentration at each trophic level
• B. degrades at first trophic level
• C. accumulates in the body fat of organism at first trophic level and does not pass to second trophic level
• D. decreases in concentration at each trophic level

Answer 1

The correct option is A magnifies in concentration at each trophic level

We use several pesticides and other chemicals like DDT, to protect our crops from diseases and pests. These chemicals are either washed down into the soil or into the water bodies. From the soil, these are absorbed by the plants along with water and minerals, and from the water bodies these are taken up by aquatic plants and animals. This is one of the ways in which they enter the food chain. As these chemicals are not degradable, these get accumulated progressively at each trophic level. As human beings occupy the top level in any food chain, the maximum concentration of these chemicals get accumulated in our bodies. This phenomenon is known as biological magnification.