Ribosome attached with rough E.R. by the help of

Options

A. Protein
B. Carbohydrate
C. Glycoprotein (Ribophorin)
D. Phosphoprotein

Answer

To answer the question "Ribosome attached with rough E.R. by the help of," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Rough Endoplasmic Reticulum (RER)**:
- The rough endoplasmic reticulum is characterized by the presence of ribosomes on its cytoplasmic surface, which gives it a "rough" appearance.

2. **Identify the Role of Ribosomes**:
- Ribosomes are the sites of protein synthesis. They can be free-floating in the cytoplasm or attached to the rough endoplasmic reticulum.

3. **Determine How Ribosomes Attach to RER**:
- Ribosomes attach to the rough endoplasmic reticulum through specific interactions. The attachment is not random; it involves certain molecules that facilitate this process.

4. **Explore the Options**:
- The options provided are:
1. Protein
2. Carbohydrate
3. Glycoprotein
4. Phosphoprotein

5. **Evaluate Each Option**:
- **Protein**: While the RER is involved in protein synthesis, proteins themselves do not assist in the attachment of ribosomes.
- **Carbohydrate**: Carbohydrates do not play a direct role in the attachment of ribosomes to the RER.
- **Glycoprotein**: This is the correct answer. Glycoproteins are molecules that consist of proteins with carbohydrate groups attached. They play a crucial role in the recognition and attachment of ribosomes to the rough endoplasmic reticulum.
- **Phosphoprotein**: Similar to the first two options, phosphoproteins do not facilitate the attachment of ribosomes.

6. **Conclusion**:
- The correct answer is **Glycoprotein**, as it helps in the attachment of ribosomes to the rough endoplasmic reticulum.

### Final Answer:
Ribosome attached with rough E.R. by the help of **Glycoprotein**.

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