Which of the Following Describes the First Step in the Replication

Question

Which of the following describes the first step in the replication cycle of retroviruses?
A) Replication of the host genome into daughter DNA molecules.
B) Integration of the viral genome into the host cell DNA.
C) Translation of the viral genome into protein.
D) Transcription of the viral genome into mRNA.
E) Reverse transcription of the viral genome into dsDNA.

Accepted Answer

The first step in the replication cycle of retroviruses is reverse transcription of the viral genome into dsDNA. This is accomplished by the enzyme reverse transcriptase, which uses the viral RNA genome as a template to synthesize a complementary DNA strand. This DNA strand is then used as a template to synthesize a second DNA strand, resulting in a double-stranded DNA molecule that can integrate into the host cell genome.