The cells of which of these organisms do not have a nucleolus ?

Options

A. Anieba
B. Blue-green algae
C. Plants
D. Paramoecium

Answer

To determine which of the given organisms does not have a nucleolus, we need to analyze the characteristics of each organism in relation to their cellular structure.

### Step-by-Step Solution:

1. **Understand What a Nucleolus Is**:
- The nucleolus is an organelle found within the nucleus of eukaryotic cells. Its primary function is to produce ribosomes.

2. **Identify the Organisms**:
- The organisms mentioned are:
- Amoeba
- Blue-green algae
- Plants
- Paramecium

3. **Classify the Organisms**:
- **Amoeba**: This is a single-celled organism classified as a eukaryote. Eukaryotic cells have a nucleus and, therefore, a nucleolus.
- **Blue-green algae**: These are prokaryotic organisms (also known as cyanobacteria). Prokaryotic cells do not have a true nucleus or nucleolus.
- **Plants**: Plants are multicellular eukaryotes, which means they have a nucleus and a nucleolus.
- **Paramecium**: This is also a single-celled eukaryote, which contains a nucleus and a nucleolus.

4. **Conclusion**:
- Among the organisms listed, blue-green algae are the only ones that do not have a nucleolus because they are prokaryotic and lack a true nucleus.

### Final Answer:
The cells of **blue-green algae** do not have a nucleolus.