Viruses use the host cell's machinery to make copies of themselves. However, some human viruses require a type of replication that humans do not normally have. 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 viral genome codes for specialised enzymes not found in the host cells.
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.

Question

Quizplus · Accepted Answer

Some viruses carry the genetic code for enzymes that human cells do not have. These enzymes allow the virus to perform necessary replication tasks within the host cell. Therefore, the virus does not need to rely on the host cell to evolve new enzymes or perform functions it cannot typically do.

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