The phenomenon by which certain pollutants (e.g. DDT) accumulate in body tissue in increasing concentration is called

Options

A. Biological magnification
B. Biological reduction
C. Bio-precipitation
D. Bio-degradation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about a phenomenon where certain pollutants, like DDT, accumulate in body tissues with increasing concentration.

2. **Identifying the Pollutant**: DDT, or Dichlorodiphenyl trichloroethane, is a synthetic pesticide known for its environmental persistence and toxicity.

3. **Explaining the Process**: When DDT enters an ecosystem, it is absorbed by primary producers (like plants or phytoplankton). These organisms are then consumed by primary consumers (herbivores), which are in turn eaten by secondary consumers (carnivores). As each trophic level consumes the lower level, the concentration of DDT increases in their tissues due to the accumulation of the substance from all the organisms they consume.

4. **Defining the Phenomenon**: The increase in concentration of pollutants like DDT at each trophic level of the food chain is known as **biological magnification**. This means that higher trophic levels have a higher concentration of the pollutant than those at lower levels.

5. **Evaluating the Options**:
- Option 1: Biological magnification - Correct, as it describes the accumulation of pollutants in increasing concentration.
- Option 2: Biological reduction - Incorrect, as it refers to the reduction of metals by microbes.
- Option 3: Bioprecipitation - Incorrect, as it involves the formation of precipitation by organisms.
- Option 4: Biodegradation - Incorrect, as it refers to the breakdown of materials by microorganisms.

6. **Conclusion**: The correct answer to the question is **biological magnification**.

**Final Answer**: The phenomenon by which certain pollutants (e.g. DDT) accumulate in body tissue in increasing concentration is called **biological magnification**.

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