Cell membrane has proteins, lipids and carbohydrates. With respect to their mutual proportions, which statement is correct ?

Options

A. All the three are in equal proportion
B. Lipids are in least proportions
C. Carbohydrates are in least proportions.
D. Proteins are in least amount

Answer

To determine the correct statement regarding the mutual proportions of proteins, lipids, and carbohydrates in the cell membrane, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Composition of the Cell Membrane**:
- The cell membrane, also known as the plasma membrane, is primarily composed of a phospholipid bilayer, along with proteins and carbohydrates.

2. **Analyzing the Proportions**:
- **Proteins**: The proportion of proteins in the cell membrane typically ranges from 20% to 70%. This indicates that proteins are a significant component of the membrane.
- **Lipids**: Lipids make up about 20% to 79% of the cell membrane. This suggests that lipids are also a major component, often more than proteins.
- **Carbohydrates**: The carbohydrate content in the cell membrane is relatively low, generally ranging from 1% to 5%. This indicates that carbohydrates are the least abundant component in the cell membrane.

3. **Evaluating the Options**:
- **Option 1**: All three are in equal proportion - This is incorrect based on the analysis above.
- **Option 2**: Lipids are in least proportion - This is incorrect as lipids are present in a higher proportion than carbohydrates.
- **Option 3**: Carbohydrates are in least proportion - This is correct since carbohydrates constitute only 1% to 5% of the cell membrane.
- **Option 4**: Proteins are in least proportion - This is incorrect as proteins are present in a significant proportion.

4. **Conclusion**:
- Based on the analysis, the correct statement is **Option 3: Carbohydrates are in least proportion**.