Proteins, present in plasma membrane are classified as integral and peripheral on the basis of :-

Options

A. Density and size
B. Ease of extractionn from membrane
C. Structure
D. Quantity

Answer

**Step-by-Step Solution:**

1. **Understanding Plasma Membrane Proteins**: The plasma membrane consists of a lipid bilayer with proteins embedded within it. These proteins play crucial roles in various cellular functions.

2. **Classification of Proteins**: The proteins in the plasma membrane are classified into two main types: integral proteins and peripheral proteins.

3. **Peripheral Proteins**:
- Peripheral proteins are located on the outer or inner surfaces of the membrane, not embedded within the lipid bilayer.
- They are also referred to as extrinsic proteins.
- The bonds between peripheral proteins and the membrane lipids are typically weaker, such as hydrogen bonds or ionic bonds.
- Peripheral proteins can be easily extracted from the membrane without disrupting the overall structure of the plasma membrane. An example of a peripheral protein is spectrin.

4. **Integral Proteins**:
- Integral proteins are embedded deeply within the lipid bilayer and are also known as intrinsic proteins.
- They are tightly bound to the membrane and cannot be easily removed without damaging the membrane structure.
- Removing integral proteins often leads to the destruction of the plasma membrane. An example of an integral protein is glycophorin.

5. **Basis of Classification**: The classification of proteins as integral or peripheral is primarily based on the ease of extraction from the membrane. Peripheral proteins can be removed easily, while integral proteins cannot.

6. **Conclusion**: Therefore, the correct answer to the question is that proteins in the plasma membrane are classified as integral and peripheral based on the ease of extraction from the membrane.

**Final Answer**: The classification of proteins in the plasma membrane as integral and peripheral is based on the ease of extraction from the membrane.

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