Biomagnification is well know for _________ and _______.

Answer

### Step-by-Step Solution:

1. **Understand Biomagnification**:
- Biomagnification is a process where the concentration of toxic substances increases in organisms at each successive trophic level of a food chain.

2. **Identify the Toxicants**:
- The question asks for specific examples of pollutants that are known for biomagnification.

3. **Recognize Common Pollutants**:
- Two well-known toxicants that exhibit biomagnification are DDT (Dichloro-Diphenyl-Trichloroethane) and mercury.

4. **Explain Why These Pollutants Magnify**:
- Both DDT and mercury are non-biodegradable, meaning they cannot be broken down by living organisms. As a result, they accumulate in the tissues of organisms and their concentration increases as one moves up the food chain.

5. **Conclude the Answer**:
- Therefore, the answer to the question is that biomagnification is well known for **DDT** and **mercury**.

### Final Answer:
Biomagnification is well known for **DDT** and **mercury**.

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