Which of the following is correct regarding AIDS causative agent … - Vidyadip

Question

Which of the following is correct regarding $AIDS$ causative agent $HIV$ ?

✓

Answer

d
(d) : $HIV$ is spherical virus with a diameter of about $90-120\ nm$. Its genome consists of a single stranded $RNA$ filament segmented into two identical filaments and associated with reverse transcriptase enzymes. The envelope consists of a lipid bilayer derived from host cell membrane and projecting knob like glycoprotein spikes. It contains two protein coats. $HIV$ is a retrovirus that attacks helper $T$ cells. Without an adequate supply of helper cells, the immune system cannot signal $B$ cells to produce antibodies to kill infected cells, thus body becomes susceptible to infections. This immune deficiency is described by the name acquired immune deficiency syndrome or $AIDS$.

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