The recent model for plasma membrane proposed by Singer and Nicolson is

Options

A. Molecular lipid model
B. Lamellar model
C. Unit membrane model
D. Fluid mosaic model

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the recent model of the plasma membrane proposed by Singer and Nicolson.

2. **Recall Previous Models**: Before discussing the Singer and Nicolson model, it's important to note that earlier models like the lamellar model and the unit membrane model were proposed by Danielli and Davson in 1935. These models described the plasma membrane as a bilayer of phospholipids.

3. **Understand the Fluid Mosaic Model**: The model proposed by Singer and Nicolson is known as the fluid mosaic model. This model describes the plasma membrane as a dynamic and flexible structure where proteins are embedded within a fluid lipid bilayer.

4. **Key Features of the Fluid Mosaic Model**:
- **Fluidity**: The lipids and proteins can move laterally within the layer, contributing to the fluid nature of the membrane.
- **Mosaic Structure**: The proteins are distributed unevenly, creating a mosaic appearance.

5. **Conclusion**: The correct answer to the question is that the recent model for the plasma membrane proposed by Singer and Nicolson is the "Fluid Mosaic Model".

**Final Answer**: The recent model for the plasma membrane proposed by Singer and Nicolson is the Fluid Mosaic Model.

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