Which of following statement about AIDS virus is incorrect ?

Options

A. AIDS virus is RNA virus
B. AIDS virus has a single copy of RNA surrounded phospholipid bilayer and protein coat
C. AZT is most commonly used drug to treat AIDS
D. AIDS virus mostly attacks T4 cells

Answer

To determine which statement about the AIDS virus is incorrect, we can analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding AIDS and HIV**:
- AIDS stands for Acquired Immunodeficiency Syndrome, which is caused by the Human Immunodeficiency Virus (HIV). This virus attacks the immune system, specifically the T-lymphocytes (T-cells), leading to a weakened immune response.

2. **Evaluating the Statements**:
- **Statement 1**: "AIDS virus is RNA virus."
- This statement is **correct**. HIV is indeed an RNA virus, specifically a single-stranded RNA virus.

- **Statement 2**: "AIDS virus has a single copy of RNA surrounded by phospholipid bilayer and protein coat."
- This statement is **incorrect**. While HIV does have a single-stranded RNA, it is surrounded by a lipid bilayer (not a bilayer in the sense of having two layers of phospholipids) and a protein coat. The phrasing is misleading as it suggests a single copy of RNA in a bilayer, which is not accurate.

- **Statement 3**: "AZT is the most commonly used drug to treat AIDS."
- This statement is **correct**. AZT (azidothymidine) is indeed one of the first drugs used to treat HIV/AIDS and is commonly prescribed.

- **Statement 4**: "AIDS virus mostly attacks T4 cells."
- This statement is **correct**. HIV primarily targets CD4+ T-cells (also known as T4 cells), which are crucial for the immune response.

3. **Conclusion**:
- The incorrect statement about the AIDS virus is the second one regarding the structure of the virus.

### Final Answer:
The incorrect statement about the AIDS virus is: "AIDS virus has a single copy of RNA surrounded by phospholipid bilayer and protein coat."

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