Which of the following groups is absolutely essential functional component of the ecosystem?

Options

A. Producers
B. Producers and herbivores
C. Producers and detrivores
D. Detritivores

Answer

To determine which group is an absolutely essential functional component of the ecosystem, we can break down the components of an ecosystem and their roles:

### Step-by-Step Solution:

1. **Understanding Ecosystem Components**: An ecosystem consists of both living (biotic) and non-living (abiotic) components. The biotic components include producers, consumers, and decomposers.

2. **Identifying Producers**: Producers, primarily plants, are organisms that can make their own food through photosynthesis. They form the base of the food chain and are essential for providing energy to other organisms in the ecosystem.

3. **Understanding Herbivores**: Herbivores are animals that consume plants (producers). While they play a crucial role in the food chain by transferring energy from producers to higher trophic levels, they are not the foundational component of the ecosystem.

4. **Identifying Decomposers**: Decomposers, such as fungi and bacteria, break down dead organic matter, returning nutrients to the soil. They are vital for nutrient cycling and maintaining soil health, but they depend on producers for organic matter to decompose.

5. **Evaluating the Options**:
- **Producers**: Essential, as they are the primary source of energy.
- **Producers and Herbivores**: Not sufficient alone, as herbivores depend on producers.
- **Producers and Decomposers**: Both are essential; producers create energy, and decomposers recycle nutrients.
- **Herbivores and Decomposers**: This combination lacks producers, which are necessary for energy input.

6. **Conclusion**: The most essential functional components of an ecosystem are the **producers and decomposers**. They are interdependent; without producers, decomposers would lack organic material to break down, and without decomposers, producers would struggle to obtain nutrients.

### Final Answer:
The correct option is **Producers and Decomposers**.

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