The endoplasmic reticulum bearing ribosomes on its surface is called:-

Answer

**Step-by-Step Solution:**

1. **Understanding Endoplasmic Reticulum (ER)**: The endoplasmic reticulum is a membrane-bound organelle found in eukaryotic cells. It plays a crucial role in the synthesis and transport of proteins and lipids.

2. **Types of Endoplasmic Reticulum**: There are two main types of endoplasmic reticulum:
- **Smooth Endoplasmic Reticulum (SER)**: This type does not have ribosomes on its surface, making it smooth. It is primarily involved in the synthesis of lipids and detoxification processes.
- **Rough Endoplasmic Reticulum (RER)**: This type has ribosomes attached to its surface, giving it a "rough" appearance. It is primarily involved in the synthesis of proteins.

3. **Identifying the Type with Ribosomes**: Since the question specifically asks for the type of endoplasmic reticulum that has ribosomes on its surface, we focus on the rough endoplasmic reticulum.

4. **Conclusion**: The endoplasmic reticulum bearing ribosomes on its surface is called the **Rough Endoplasmic Reticulum (RER)**.

**Final Answer**: Rough Endoplasmic Reticulum (RER)

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