Which one does not have eukaryotic organisation ?

Options

A. Green algae
B. Blue green algae
C. Red algae
D. Golden brown algae.

Answer

To answer the question "Which one does not have eukaryotic organization?" we will analyze the given options based on their cellular organization.

### Step-by-Step Solution:

1. **Understanding Eukaryotic Organization**:
- Eukaryotic organisms are characterized by having a well-defined nucleus enclosed by a nuclear membrane and membrane-bound organelles. They are typically multicellular, although some can be unicellular.

2. **Analyzing the Options**:
- **Green Algae (Chlorophyceae)**:
- Green algae are part of the kingdom Plantae and have a eukaryotic organization. They possess a well-defined nucleus and membrane-bound organelles.
- **Blue Green Algae (Cyanobacteria)**:
- Blue green algae, also known as cyanobacteria, are prokaryotic organisms. They lack a defined nucleus and membrane-bound organelles, which means they do not have eukaryotic organization.
- **Red Algae (Rhodophyceae)**:
- Red algae are also members of the kingdom Plantae and possess eukaryotic characteristics, including a defined nucleus and organelles.
- **Golden Brown Algae**:
- Golden brown algae are eukaryotic as well, belonging to the kingdom Plantae and having a defined nucleus and organelles.

3. **Conclusion**:
- After analyzing all the options, we find that the only organism that does not have a eukaryotic organization is **Blue Green Algae (Cyanobacteria)**.

### Final Answer:
The correct answer is **B. Blue Green Algae**.

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