Cell membrane is

Options

A. Unilaminar
B. Bilaminer
C. Trilaminer
D. Quadrilaminar

Answer

**Step-by-Step Solution:**

1. **Understanding the Cell Membrane Structure**: The cell membrane, also known as the plasma membrane, is crucial for maintaining the integrity of the cell. It acts as a barrier between the internal environment of the cell and the external surroundings.

2. **Identifying the Composition**: The cell membrane is primarily composed of a phospholipid bilayer. This bilayer consists of two layers of phospholipids, which are molecules that have a hydrophilic (water-attracting) "head" and two hydrophobic (water-repelling) "tails".

3. **Analyzing the Layers**: In the phospholipid bilayer:
- The outer layer consists of hydrophilic heads facing the external environment.
- The inner layer consists of hydrophilic heads facing the cytoplasm of the cell.
- The hydrophobic tails of the phospholipids are sandwiched between these two layers.

4. **Determining the Correct Option**: Given the structure of the cell membrane:
- **Unilaminar**: This would imply a single layer, which is incorrect.
- **Bilaminar**: This suggests two layers, which does not account for the hydrophilic heads on both sides.
- **Trilaminar**: This indicates three distinct layers: two hydrophilic layers and one hydrophobic layer in between, which accurately describes the cell membrane.
- **Quadrilaminar**: This would suggest four layers, which is also incorrect.

5. **Conclusion**: The correct answer is **Trilaminar**, as the cell membrane consists of two layers of hydrophilic heads and one layer of hydrophobic tails.

**Final Answer**: The cell membrane is **Trilaminar**.

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