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 the Terrestrial Ecosystem**: A terrestrial ecosystem is one that exists on land, where various organisms interact with each other and their environment.

2. **Energy Flow in Ecosystems**: Energy flow in an ecosystem begins with the sun, which provides energy for photosynthesis. Plants (producers) convert this solar energy into chemical energy.

3. **Trophic Levels**: In a typical food chain, energy flows through different trophic levels:
- **Producers**: Plants (e.g., grass) convert sunlight into energy.
- **Primary Consumers**: Herbivores (e.g., grasshoppers) eat the plants.
- **Secondary Consumers**: Carnivores (e.g., frogs) eat the herbivores.
- **Tertiary Consumers**: Higher-level carnivores (e.g., snakes) eat the secondary consumers.
- **Quaternary Consumers**: Apex predators (e.g., hawks) eat the tertiary consumers.

4. **Energy Transfer**: At each trophic level, energy is transferred from one organism to another. However, not all energy is passed on; a significant portion is lost as heat, used for metabolic processes, or remains in the form of waste.

5. **Role of Decomposers**: When organisms die, their bodies become part of the detritus (dead organic matter). Decomposers (e.g., bacteria and fungi) break down this detritus, returning nutrients to the soil.

6. **Detritus Food Chain**: The large fraction of energy in a terrestrial ecosystem flows through the detritus food chain. This is because decomposers play a crucial role in recycling nutrients, which is essential for the growth of plants and the continuation of the ecosystem.

7. **Conclusion**: Therefore, in a terrestrial ecosystem, the large fraction of energy flows through the detritus food chain, highlighting the importance of decomposers in maintaining ecological balance.

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