Reverse transcriptase in RNA and DNA conversion

What is reverse transcriptase?
A protein that can convert RNA to DNA (so transcriptase in reverse)
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How is retrovirus different from other viruses?
Its genome is RNA based versus DNA based and in order for it to highjack our cells, they require that reverse transcriptase step before they can highjack the machinery of the host cell.
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How does a retrovirus infect a cell and reproduce itself?
In HIV specifically, the gp120 recognizes and binds the CD4 protein on the T Helper cell surface.
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What is a T cell?
They recognize human cells that have already been infected by a foreign virus or bacteria => cellular immune response. They kill already infected cells. Their cell surface have a protein called CD8.
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As time progresses, why do the cytotoxic T cells stop responding to the HIV infection?
They stop responding to the infection because less TC cells are being produced and more TH cells are being infected.