The protein necessary for the organization of ribosomal subunits are synthesized by

Options

A. Golgi complex
B. Peroxysomes
C. Ribosomes
D. Smooth endoplasmic reticulum

Answer

To solve the question regarding which organelle synthesizes the protein necessary for the organization of ribosomal subunits, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Ribosomal Subunits**:
Ribosomes are made up of ribosomal RNA (rRNA) and proteins. The assembly of these components forms the ribosomal subunits, which are essential for protein synthesis in cells.

2. **Identifying the Role of Ribosomal Proteins**:
Ribosomal proteins are synthesized in the cell and then transported to the nucleolus, where they combine with rRNA to form the ribosomal subunits.

3. **Locating the Site of Protein Synthesis**:
The synthesis of ribosomal proteins occurs in the cytoplasm. The organelles responsible for synthesizing proteins in the cytoplasm are ribosomes.

4. **Evaluating the Options**:
- **Golgi Complex**: Primarily involved in modifying, sorting, and packaging proteins.
- **Peroxisomes**: Involved in lipid metabolism and detoxification, not protein synthesis.
- **Ribosomes**: The site of protein synthesis, including ribosomal proteins.
- **Smooth Endoplasmic Reticulum (SER)**: Involved in lipid synthesis and detoxification, not directly in protein synthesis.

5. **Conclusion**:
Based on the understanding that ribosomes are responsible for synthesizing proteins, including those necessary for the organization of ribosomal subunits, the correct answer is **ribosomes**.

### Final Answer:
The protein necessary for the organization of ribosomal subunits is synthesized by **ribosomes**.