One of the following is an important constituent of the cell membrane

Options

A. Cellulose
B. Calcium pectate
C. Phospholipids
D. Lignin

Answer

To determine the important constituent of the cell membrane from the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question presents four options:
- Option 1: Cellulose
- Option 2: Calcium Pectate
- Option 3: Phospholipids
- Option 4: Lignin

2. **Evaluate Option 1 - Cellulose**:
- Cellulose is primarily a component of the plant cell wall, not the cell membrane. Therefore, this option is incorrect.

3. **Evaluate Option 2 - Calcium Pectate**:
- Calcium Pectate is also found in the plant cell wall, specifically in the middle lamella, which helps in cell adhesion. Thus, this option is also incorrect.

4. **Evaluate Option 3 - Phospholipids**:
- Phospholipids are a major component of the cell membrane. They form a bilayer that provides structure and regulates the movement of substances in and out of the cell. This option is correct.

5. **Evaluate Option 4 - Lignin**:
- Lignin is an organic polymer found in the cell wall that provides rigidity and strength. It is not a component of the cell membrane, making this option incorrect.

6. **Conclusion**:
- The correct answer is **Option 3: Phospholipids**, as they are essential constituents of the cell membrane.

### Final Answer:
**Phospholipids are an important constituent of the cell membrane.**

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