An analysis of soil sample revealed 0.1 mg of a pesticide and 1 mg of the same pesticide was found in grains. However in the adipose tissue of birds the concentration was 2 mg. The reason for this is the phenomenon known as

Options

A. Bio-absorption
B. Bio-translocation
C. Bio-magnification
D. Bio-multiplication

Explanation

To solve the question regarding the phenomenon observed in the concentration of pesticide in the soil, grains, and adipose tissue of birds, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Concentrations**:
- Soil: 0.1 mg of pesticide
- Grains: 1 mg of pesticide
- Adipose tissue of birds: 2 mg of pesticide

2. **Understand the Concept of Food Chain**:
- In a food chain, energy and nutrients are transferred from one trophic level to another. Here, soil (producers) provides nutrients to grains (primary consumers), which are then consumed by birds (secondary consumers).

3. **Analyze the Increase in Concentration**:
- The concentration of pesticide increases as we move from soil to grains (0.1 mg to 1 mg) and then to birds (1 mg to 2 mg). This indicates that the pesticide is accumulating in organisms as they consume contaminated food.

4. **Define Biomagnification**:
- Biomagnification refers to the process where the concentration of toxic substances increases in organisms at each successive trophic level of a food chain. This occurs because organisms at higher trophic levels consume multiple organisms from lower levels, leading to a higher accumulation of toxins.

5. **Conclude with the Correct Answer**:
- The phenomenon observed in this scenario, where the concentration of pesticide increases from soil to grains to birds, is known as **biomagnification**.

### Final Answer:
The reason for the increased concentration of pesticide in the adipose tissue of birds is the phenomenon known as **biomagnification**.

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