Sum is the source of energy in following ecosystems except

Options

A. Pond ecosystem
B. Grazing food chain
C. Deep sea hydrothermal ecosystem
D. Scrub forest

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which ecosystem does not primarily rely on the sun as the source of energy.

2. **Identifying Ecosystems**: The ecosystems mentioned are:
- Pond ecosystem
- Grazing food chain
- Deep sea hydrothermal ecosystem
- Scrub forest

3. **Analyzing Each Ecosystem**:
- **Pond Ecosystem**: In this ecosystem, sunlight penetrates the water, allowing photosynthetic organisms like phytoplankton to thrive. Therefore, the sun is a primary energy source here.

- **Grazing Food Chain**: This is typically found on land where plants (producers) use sunlight to produce food through photosynthesis, making the sun the main energy source.

- **Deep Sea Hydrothermal Ecosystem**: This ecosystem is characterized by extreme conditions where sunlight does not penetrate. Instead of relying on sunlight, organisms here often depend on chemosynthesis, using chemicals from hydrothermal vents as their energy source. Thus, the sun is not the major energy source in this ecosystem.

- **Scrub Forest**: This ecosystem has ample sunlight, allowing green plants to perform photosynthesis and produce their own food. Hence, the sun is a significant energy source here.

4. **Conclusion**: Based on the analysis, the deep sea hydrothermal ecosystem is the only one that does not primarily depend on the sun for energy. Therefore, the correct answer is the deep sea hydrothermal ecosystem.

**Final Answer**: The source of energy in the following ecosystems except the deep sea hydrothermal ecosystem.

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