In a terrestrial ecosystem the large fraction of energy flows through

Options

A. detritus food chain
B. grazing food chain
C. herbivores
D. carnivores

Explanation

**Step-by-Step Solution:**

1. **Understanding Terrestrial Ecosystems**:
- A terrestrial ecosystem refers to land-based ecosystems, which include forests, grasslands, deserts, and tundras. These ecosystems are characterized by their flora and fauna, and they rely on various energy flow mechanisms.

2. **Energy Flow in Ecosystems**:
- Energy flow in ecosystems can occur through different food chains, primarily the grazing food chain and the detritus food chain. The grazing food chain starts with producers (like plants) and moves up through herbivores to carnivores. The detritus food chain, on the other hand, begins with decomposing organic matter.

3. **Detritus Food Chain**:
- The detritus food chain is crucial in terrestrial ecosystems because it involves decomposers such as bacteria and fungi. These organisms break down dead organic matter, recycling nutrients back into the soil, which supports plant growth.

4. **Significance of Decomposers**:
- Decomposers play a vital role in energy flow as they help in the breakdown of organic materials, making nutrients available for primary producers. This process is essential for maintaining the health and sustainability of terrestrial ecosystems.

5. **Conclusion**:
- Given the importance of decomposers in recycling nutrients and facilitating energy flow in terrestrial ecosystems, the large fraction of energy flows through the detritus food chain. Therefore, the correct answer to the question is option number 1, the detritus food chain.

**Final Answer**: The large fraction of energy flows through the detritus food chain in a terrestrial ecosystem.

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