Outer envelope of HIV consists of

Options

A. RNA coat
B. Phospholipid bilayer studded with glycoproteins CCR5 and CXCR4
C. Phospholipid bilayer studded with glycoproteins Gp120 and Gp41
D. `P_24` protein coat

Answer

To answer the question about the outer envelope of HIV, we can break down the information as follows:

### Step-by-Step Solution:

1. **Understanding HIV**:
- HIV stands for Human Immunodeficiency Virus, which is responsible for causing AIDS (Acquired Immunodeficiency Syndrome).

2. **Structure of HIV**:
- The outer envelope of HIV is crucial for its function and interaction with host cells.

3. **Composition of the Outer Envelope**:
- The outer envelope is primarily made up of a **phospholipid bilayer**. This bilayer is a fundamental component of cell membranes, providing structural integrity.

4. **Presence of Glycoproteins**:
- Embedded within this phospholipid bilayer are glycoproteins, specifically **GP120** and **GP41**. These proteins play a critical role in the virus's ability to infect host cells.

5. **Function of GP120 and GP41**:
- **GP120** is responsible for binding to CD4 receptors on the surface of immune cells, while **GP41** facilitates the fusion of the viral envelope with the host cell membrane, allowing the virus to enter the cell.

6. **Conclusion**:
- Therefore, the outer envelope of HIV consists of a phospholipid bilayer along with glycoproteins (GP120 and GP41).

### Final Answer:
The outer envelope of HIV consists of a phospholipid bilayer and glycoproteins (GP120 and GP41).

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