Ribosomes develop from

Options

A. Nucleus
B. Nucleolus
C. Endoplasmic reticulum
D. Mitochondria

Answer

### Step-by-Step Solution:

1. **Understanding Ribosomes**: Ribosomes are essential cellular structures that serve as the site for protein synthesis. They play a crucial role in translating messenger RNA (mRNA) into proteins.

2. **Identifying the Origin of Ribosomes**: The question asks where ribosomes develop from. To answer this, we need to consider the cellular structures involved in ribosome production.

3. **Analyzing the Options**:
- **Nucleus**: The nucleus is the central part of the cell that contains genetic material (DNA). While it is crucial for cell function, ribosomes do not develop directly from the nucleus itself.
- **Nucleolus**: The nucleolus is a dense, spherical structure located within the nucleus. It is specifically involved in the synthesis and processing of ribosomal RNA (rRNA) and the assembly of ribosomal subunits. This makes it a strong candidate for the origin of ribosomes.
- **Endoplasmic Reticulum**: The endoplasmic reticulum (ER) is involved in the synthesis of proteins and lipids but does not directly produce ribosomes.
- **Mitochondria**: Mitochondria are known as the powerhouse of the cell, generating ATP. They do not play a role in ribosome development.

4. **Conclusion**: Based on the analysis, the correct answer is that ribosomes develop from the **nucleolus**.

### Final Answer:
Ribosomes develop from the **nucleolus**.

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