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Consider the following four statements (...

Consider the following four statements (a-d) about AIDS/ HIV and select the option which includes all the correct ones only.
a) Caracterised by decrease in number of killer T- cells
b) HIV virus has 2 identical molecule of ds RNAs
c) AIDS spread through touch, physical contact, hugging, kissing
d) There is always a time lag between the infection and appearance of AIDS symptoms.

A

Statements b & d

B

Statement a, b & d

C

Statements b only

D

Statement d only

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the statements about AIDS/HIV, we will analyze each statement one by one to determine which are correct. ### Step-by-Step Solution: 1. **Statement a**: "Characterised by decrease in number of killer T-cells." - **Analysis**: This statement is incorrect. AIDS is characterized by a decrease in the number of T-helper cells (CD4+ T cells), not killer T-cells (CD8+ T cells). The decrease in T-helper cells weakens the immune response. 2. **Statement b**: "HIV virus has 2 identical molecules of ds RNAs." - **Analysis**: This statement is also incorrect. HIV is a retrovirus that contains two identical single-stranded RNA molecules, not double-stranded RNA. 3. **Statement c**: "AIDS spread through touch, physical contact, hugging, kissing." - **Analysis**: This statement is incorrect. AIDS is primarily transmitted through blood, sexual contact, and from mother to child during childbirth or breastfeeding. It is not spread through casual contact like hugging or kissing. 4. **Statement d**: "There is always a time lag between the infection and appearance of AIDS symptoms." - **Analysis**: This statement is correct. After HIV infection, there can be a significant time lag (often several years) before the symptoms of AIDS appear, as the virus can remain latent while it replicates and depletes T-helper cells. ### Conclusion: The only correct statement among the four is **Statement d**. Therefore, the option that includes all the correct statements is the one that states only **Statement d** is correct. ### Final Answer: **Correct Option**: Statement D only. ---
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