Question

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

Hint: DDT increases as it moves up a food chain. DDT is a fat-soluble which means animals store it in fatty tissues.Full form of DDT is dichloro-diphenyl-trichloroethane.

Complete answer : Metabolic studies in insects, in mice and in a modern eco-system with several food chains have shown that DDT analogues with substituent groups readily attacked by multi-function oxidases undergo a substantial degree of biological degradation. It also takes a relatively long amount of time to breakdown.Thus, if a predator consumes multiple organisms and each organism has a small amount of DDT, the amount of DDT in the predator is going to be the result of all those small amounts combined.

Additional information : Non-degradable pollutants are the pollutants which cannot be broken down into simpler substances. Some of these pollutants like metals create problems because they are toxic and persistent in the environment. Fat-soluble pollutants are also called lipid soluble pollutants. They include tetraethyllead compounds and DDT and these pollutants are stored in the body's fat. These are required when the fatty tissues are used for energy and the compounds which are released cause acute poisoning.

Thus, the correct answer is option A. i.e. Magnifies in concentration at each trophic level.

Notes: During the Biomagnification, the concentration of non-degradable pesticides like DDT goes on increasing along the food chain and highest values occur in the consumers at the trophic level. Biomagnification is the accumulation of increasing concentration of lipophilic pesticides in the top members of the food chain.