Which is correctly matched? 1. Arsenic poisoning- Black foot disease. 2. Secondary Effluent treatment- Biological process. 3. Pyrolysis- Solid soil waste disposal 4. Tubifex- Water pollution indicator 5. Biomagnification- Degradable pollutants
1, 2, 3, 5
1, 3, 4, 5
2, 3, 4, 5
1, 2, 3, 4
The correct option is D 1, 2, 3, 4 Biomagnification refers to increase in concentration of the toxicant at successive trophic levels. This happens because a toxic substance accumulated by an organism cannot be metabolised or excreted (non degradable), and is thus passed on to the next higher trophic level. This phenomenon is well known for mercury and DDT. Biological magnification often refers to the process whereby certain substances such as pesticides or heavy metals move up the food chain, work their way into rivers or lakes, and are eaten by aquatic organisms such as fish, which in turn are eaten by large birds, animals or humans. The substances become concentrated in tissues or internal organs as they move up the chain.