The cell brain shows extensive and continuous tiny tubular structures on its outer membrane which is

Options

A. Endoplasmic reticulum
B. Golgi complex
C. Microtubules
D. Chromatin

Answer

To solve the question regarding the extensive and continuous tiny tubular structures on the outer membrane of the cell brain, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure Described**: The question refers to "extensive and continuous tiny tubular structures" on the outer membrane of the cell brain. The term "cell brain" typically refers to the nucleus of the cell.

2. **Recall Cell Organelles**: We need to consider the various organelles associated with the nucleus. The options given are:
- Endoplasmic Reticulum (ER)
- Golgi Complex
- Microtubule
- Chromatin

3. **Analyze Each Option**:
- **Endoplasmic Reticulum (ER)**: The ER is known for its extensive network of tubular structures. It is continuous with the nuclear envelope and can be rough (with ribosomes) or smooth (without ribosomes). This matches the description in the question.
- **Golgi Complex**: The Golgi apparatus is involved in modifying, sorting, and packaging proteins but does not have a tubular structure that is continuous with the nucleus.
- **Microtubule**: Microtubules are part of the cytoskeleton and do not form a continuous structure with the nucleus.
- **Chromatin**: Chromatin consists of DNA and proteins within the nucleus and does not represent a tubular structure.

4. **Conclusion**: Based on the analysis, the extensive and continuous tiny tubular structures on the outer membrane of the cell brain (nucleus) correspond to the Endoplasmic Reticulum. Therefore, the correct answer is **Endoplasmic Reticulum**.

### Final Answer:
The correct answer is **Endoplasmic Reticulum**.

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