Rough endoplasmic reticulum differs from smooth endoplasmic reticulum due to the presence of

Options

A. DNA
B. Nucleus
C. Ribosomes
D. Ergastic substance

Explanation

### Step-by-Step Solution:

1. **Understanding the Endoplasmic Reticulum (ER)**: The endoplasmic reticulum is an organelle in eukaryotic cells that plays a crucial role in the synthesis of proteins and lipids. It comes in two forms: rough and smooth.

2. **Identifying the Rough Endoplasmic Reticulum (RER)**: The rough endoplasmic reticulum is characterized by its rough appearance, which is due to the presence of ribosomes on its surface. These ribosomes are the sites of protein synthesis.

3. **Identifying the Smooth Endoplasmic Reticulum (SER)**: In contrast, the smooth endoplasmic reticulum lacks ribosomes on its surface, giving it a smooth appearance. The SER is primarily involved in the synthesis of lipids and the storage of fats.

4. **Key Difference**: The main difference between the rough and smooth endoplasmic reticulum is the presence of ribosomes. Ribosomes are not found on the smooth endoplasmic reticulum, which is why it is termed "smooth."

5. **Conclusion**: Therefore, the rough endoplasmic reticulum differs from the smooth endoplasmic reticulum due to the presence of ribosomes.

### Final Answer:
The rough endoplasmic reticulum differs from the smooth endoplasmic reticulum due to the presence of **ribosomes**.

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