How many types of proteins does membrane contain?

Explanation

To answer the question "How many types of proteins does the membrane contain?", we can break it down step by step:

### Step-by-Step Solution:

1. **Understanding the Plasma Membrane**: The plasma membrane is a crucial component of cells, composed mainly of a lipid bilayer with embedded proteins.

2. **Fluid Mosaic Model**: The structure of the plasma membrane is best explained by the Fluid Mosaic Model proposed by Singer and Nicholson in 1972. This model describes the membrane as a mosaic of various proteins floating in or on the fluid lipid bilayer.

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