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 step by step:

### Step-by-Step Solution:

1. **Understanding HIV Structure**:
- HIV stands for Human Immunodeficiency Virus. It is important to know that this virus has a specific structure that includes an outer envelope.

2. **Components of HIV**:
- The HIV virus is composed of single-stranded RNA, which is the genetic material of the virus. This RNA is encapsulated within a protein shell.

3. **Layers of the Virus**:
- The HIV virus has two main layers: an inner layer (capsid) and an outer layer (envelope).
- The inner layer is known as the capsid, which is made up of proteins.

4. **Outer Envelope Composition**:
- The outer envelope of HIV is primarily made up of a **phospholipid bilayer**. This bilayer is crucial for the virus's ability to infect host cells.
- The phospholipid bilayer is **studded with glycoproteins**, which play a significant role in the virus's interaction with host cells.

5. **Types of Glycoproteins**:
- There are two main types of glycoproteins associated with the HIV envelope:
- **GP120**: This is a surface glycoprotein that is essential for the virus's ability to attach to and enter host cells.
- **GP41**: This is a transmembrane glycoprotein that aids in the fusion of the viral envelope with the host cell membrane.
- Both GP120 and GP41 are derived from a precursor glycoprotein known as GP160.

6. **Conclusion**:
- Therefore, the outer envelope of HIV consists of a **phospholipid bilayer** that is studded with glycoproteins, specifically GP120 and GP41.

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

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