According to fluid mosaic model, plasma membrane is composed of

Options

A. phospholipids and oligosaccharides
B. phospholipids and hemicellulose
C. phospholipids and integral proteins
D. phospholipids , extrinsic proteins and intrinsic proteins

Explanation

**Step-by-Step Solution:**

1. **Understanding the Fluid Mosaic Model**: The fluid mosaic model describes the structure of the plasma membrane as a mosaic of various components that are fluid in nature. This model was proposed by scientists Singer and Nicholson.

2. **Identifying Components of the Plasma Membrane**: According to this model, the plasma membrane is primarily composed of phospholipids, proteins, and carbohydrates. The phospholipids form a bilayer, while proteins are embedded within this bilayer.

3. **Analyzing the Options**:
- **Option A**: Phospholipids and oligosaccharides - Oligosaccharides are not a primary structural component of the plasma membrane.
- **Option B**: Phospholipids and hemicellulose - Hemicellulose is also not a component of the plasma membrane.
- **Option C**: Phospholipids and integral proteins - Integral proteins are indeed a part of the membrane, but this option does not include extrinsic proteins.
- **Option D**: Phospholipids, extrinsic proteins, and intrinsic proteins - This option correctly identifies the components of the plasma membrane.

4. **Conclusion**: The most appropriate answer is option D, which includes phospholipids, intrinsic proteins (also known as integral proteins), and extrinsic proteins.

5. **Final Answer**: Therefore, according to the fluid mosaic model, the plasma membrane is composed of **phospholipids, intrinsic proteins, and extrinsic proteins** (Option D).

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