The average thickness of plasma membrane is

Options

A. `70Å`
B. `75-100Å`
C. `100-150Å`
D. `200Å`

Answer

**Step-by-Step Solution:**

1. **Understanding Plasma Membrane**: The plasma membrane is a crucial component of cells that acts as a selective barrier, regulating what enters and exits the cell.

2. **Composition of Plasma Membrane**: The plasma membrane is primarily composed of a lipid bilayer, which includes proteins, carbohydrates (sugar molecules), and cholesterol. This composition is essential for its function and structure.

3. **Measuring Thickness**: The thickness of the plasma membrane is very small and requires advanced tools for measurement. An electron microscope is used for this purpose because it can visualize structures at a much finer scale than a regular light microscope.

4. **Thickness Range**: Research and measurements using electron microscopes have shown that the average thickness of the plasma membrane ranges from 75 to 100 angstroms.

5. **Conversion to Meters**: To understand this measurement in more familiar units, it is important to note that 1 angstrom is equal to \(10^{-10}\) meters. Therefore, the thickness in meters would be between \(75 \times 10^{-10}\) meters and \(100 \times 10^{-10}\) meters.

6. **Conclusion**: Based on the information gathered, the average thickness of the plasma membrane is between 75 to 100 angstroms.

**Final Answer**: The average thickness of the plasma membrane is 75 to 100 angstroms.

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