Arrange the following steps involved in replication of retrovirus in correct sequence.
A. Viral RNA is introduced into animal cell
B. New viral RNA is produced by infected cell
C. Viral DNA is produced by reverse transcriptase
D. Virus infects normal animal cell
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → D, A, C, B
A retrovirus such as HIV has RNA as its genetic material. It uses the enzyme reverse transcriptase to make DNA from its RNA, which is the reverse of the usual direction of the flow of information.
(D) Virus infects normal animal cell — this comes first. The virus must first get into a host cell, for example a macrophage in the case of HIV.
(A) Viral RNA is introduced into animal cell — this comes second. Inside the cell the viral RNA genome is set free.
(C) Viral DNA is produced by reverse transcriptase — this comes third. The RNA genome is copied into viral DNA, which then gets built into the DNA of the host cell.
(B) New viral RNA is produced by infected cell — this comes last. The viral DNA in the host DNA directs the cell to make new viral RNA and virus particles.
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AIDS – …
Figure 7.6 Replication of retrovirus