Agranular ER of muscle cells is also called as

Options

A. Sarcoplasmic reticulum
B. Nissome and granules
C. Desmotubules
D. Dictyosome

Answer

To answer the question "Agranular ER of muscle cells is also called as," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Agranular Endoplasmic Reticulum**:
- The endoplasmic reticulum (ER) can be classified into two types: granular (rough) and agranular (smooth). The agranular ER lacks ribosomes on its surface.

2. **Identifying the Type of Agranular ER in Muscle Cells**:
- In muscle cells, the specific type of agranular ER is involved in important functions, particularly in muscle contraction.

3. **Naming the Agranular ER in Muscle Cells**:
- The agranular ER in muscle cells is known as the **sarcoplasmic reticulum**. This structure plays a crucial role in regulating calcium ion concentration, which is essential for muscle contraction.

4. **Eliminating Other Options**:
- Other terms mentioned, such as mesosomes, desmotubules, and dictyosomes, refer to different cellular structures and are not related to the agranular ER in muscle cells. Mesosomes are associated with prokaryotic cells, desmotubules connect plant cells, and dictyosomes are synonymous with the Golgi apparatus.

5. **Conclusion**:
- Therefore, the correct answer to the question is that the agranular ER of muscle cells is called the **sarcoplasmic reticulum**.

### Final Answer:
The agranular ER of muscle cells is also called the **sarcoplasmic reticulum**.

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