Which one of the following group of organisms can represent every trophic level in a ecosystem?

Options

A. Lice
B. Fungi
C. Bacteria
D. None of these

Answer

To solve the question of which group of organisms can represent every trophic level in an ecosystem, we can follow these steps:

### Step 1: Understand Trophic Levels
Trophic levels in an ecosystem include:
- **Producers (Autotrophs)**: Organisms that produce their own food, such as plants and some bacteria.
- **Primary Consumers (Herbivores)**: Organisms that eat producers.
- **Secondary Consumers (Carnivores)**: Organisms that eat primary consumers.
- **Tertiary Consumers**: Organisms that eat secondary consumers.
- **Decomposers**: Organisms that break down dead organic matter, returning nutrients to the ecosystem.

### Step 2: Analyze the Options
The question provides four options:
1. Lies
2. Fungies (Fungi)
3. Bacteria
4. None of the above

### Step 3: Evaluate Each Option
- **Lies**: This is not a biological group and does not represent any trophic level.
- **Fungi**: Fungi primarily act as decomposers. They do not represent all trophic levels since they do not function as producers or consumers in the traditional sense.
- **Bacteria**: Bacteria can function in multiple roles. They can be:
- **Autotrophic**: Some bacteria can perform photosynthesis (phototrophic) or chemosynthesis (chemoautotrophic).
- **Heterotrophic**: Many bacteria can act as decomposers or even as parasites, thus representing different consumer levels.
- **None of the above**: This option suggests that none of the listed groups can represent every trophic level, which is incorrect since bacteria can.

### Step 4: Conclusion
Based on the analysis, the group of organisms that can represent every trophic level in an ecosystem is **Bacteria**.

### Final Answer
The correct answer is **Option 3: Bacteria**.

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