Which one of the following organisms is not an example of eukaryotic cells

Options

A. Amoeba proteus
B. Paramecium caudatum
C. Escherichia coli
D. Euglena viridis

Answer

To determine which organism is not an example of eukaryotic cells, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Eukaryotic Cells**: Eukaryotic cells are characterized by having a well-defined membrane-bound nucleus and membrane-bound organelles (like mitochondria and chloroplasts).

2. **List the Organisms**: The organisms given in the question are:
- Amoeba proteus
- Paramecium caudatum
- Escherichia coli
- Euglena viridis

3. **Identify Eukaryotic Organisms**:
- **Amoeba proteus**: This is a type of protozoan and is a eukaryote.
- **Paramecium caudatum**: This is also a protozoan and is a eukaryote.
- **Euglena viridis**: This is a protist and is a eukaryote.

4. **Identify Prokaryotic Organism**:
- **Escherichia coli**: This is a bacterium, which is a prokaryote. Prokaryotic cells do not have a membrane-bound nucleus or organelles.

5. **Conclusion**: Since Escherichia coli is the only organism listed that is not a eukaryote, it is the correct answer to the question.

### Final Answer:
**Escherichia coli** is not an example of eukaryotic cells.

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