The cell structures that are mainly nucleoproteinaceous in nature, usually have

Options

A. single membrane
B. double membrane
C. no membrane
D. any of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms**: The question refers to "nucleoproteinaceous" structures in cells. This term can be broken down into two parts: "nucleo," which relates to nucleic acids (like DNA and RNA), and "proteinaceous," which refers to proteins.

2. **Identifying the Structures**: In cells, the structures that contain both nucleic acids and proteins are primarily ribosomes. Ribosomes are essential for protein synthesis, as they translate messenger RNA (mRNA) into proteins.

3. **Membrane Characteristics**: The question asks about the type of membrane associated with these nucleoproteinaceous structures. Ribosomes are unique in that they do not have a membrane surrounding them. This distinguishes them from other organelles like mitochondria and chloroplasts, which are double-membraned, or the endoplasmic reticulum, which is single-membraned.

4. **Conclusion**: Based on the characteristics of ribosomes, we conclude that the cell structures that are mainly nucleoproteinaceous in nature usually have **no membrane**.

5. **Final Answer**: The correct option is **C: no membrane**.

---