The prokaryotic cells have

Options

A. one envelope system
B. two envelope system
C. three envelope system
D. no envelope system

Answer

### Step-by-Step Solution:

1. **Understanding Prokaryotic Cells**: Prokaryotic cells are considered primitive cells. They are simpler in structure compared to eukaryotic cells.

2. **Nucleus in Prokaryotic Cells**: Prokaryotic cells have a "false nucleus," meaning that their genetic material (DNA) is not enclosed within a membrane-bound nucleus. Instead, the DNA is located freely in the cytoplasm.

3. **Envelope System**: The term "envelope system" refers to the membranes that surround the cell and its organelles. In prokaryotic cells, there is only one membrane system.

4. **Presence of Membranes**: In prokaryotic cells, the only membrane present is the plasma membrane, which forms the outer covering of the cell. There are no additional internal membranes surrounding organelles, as seen in eukaryotic cells.

5. **Conclusion**: Therefore, prokaryotic cells have a **one envelope system** because they possess only the plasma membrane as their outer membrane and lack membrane-bound organelles.

### Final Answer:
Prokaryotic cells have a **one envelope system**.

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