question_answer 11)

What is the mechanism by which the AIDS virus causes deficiency of immune system of the infected person? 

Answer:

HIV attacks the helper-T cells. Inside the host cell, viral RNA synthesizes single stranded DNA on it in the presence of enzyme reverse transcriptase. Single stranded DNA separates from viral-RNA and forms its complimentary copy to form double stranded DNA which is incorporated into host's cell DNA. The viral DNA transcribes large number of RNA particles, each of which gets surrounded by a proteinous capsid to complete viral particles. Finally, the host helper T-cell is lysed and many HIV viruses are released. Each of these infects new Helper T- cells. So there is progressive decrease in the number of Helper-T-cells.