Viruses use the host's machinery to make copies of themselves.However,some human viruses require a type of replication that humans do not normally do.For example,humans normally do not have the ability to convert RNA into DNA.How can these types of viruses infect humans,when human cells cannot perform a particular role that the virus requires?
A)The virus causes mutations in the human cells,resulting in the formation of new enzymes that are capable of performing these roles.
B)The virus has in its own genome the code for any specialized enzymes that the host does not have.
C)The virus infects only those cells and species that can perform all the replication roles necessary.
D)Viruses can stay in a quiescent state until the host cell evolves this ability.
E)All of the above have been frequently observed.

Question

Quizplus · Accepted Answer

Some viruses carry their own specialized enzymes to perform necessary roles that the host does not have. This is true for retroviruses, which use a reverse transcriptase enzyme to convert their RNA genome into DNA for integration into the host's genome.

Viruses Use the Host's Machinery to Make Copies of Themselves