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

Options

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

Answer

To determine which organism is not an example of eukaryotic cells, we need to understand the difference between prokaryotic and eukaryotic cells.

### Step-by-Step Solution:

1. **Understand the Definitions**:
- **Prokaryotic Cells**: These are simple, unicellular organisms that lack a nucleus and membrane-bound organelles. Examples include bacteria and archaea.
- **Eukaryotic Cells**: These are more complex cells that have a nucleus and membrane-bound organelles. Examples include plants, animals, fungi, and protists.

2. **Identify the Organisms**:
- Look at the list of organisms provided in the question. Common examples might include:
- Bacteria
- Fungi
- Plants
- Animals

3. **Classify Each Organism**:
- **Bacteria**: Prokaryotic
- **Fungi**: Eukaryotic
- **Plants**: Eukaryotic
- **Animals**: Eukaryotic

4. **Determine the Answer**:
- From the classifications, we see that **Bacteria** is the only organism that is not an example of eukaryotic cells. Therefore, the answer to the question is **Bacteria**.

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