Viruse Replicates by... attaching itself to a host cell and injects its genetic material into it. During replication and assembly the viral DNA or RNA incorporates itself into the host cell's genetic material and induces it to replicate the viralgenome.
Viruses are not considered living organisms because….they lack many of the properties that scientists associate with living organisms like not being able to reproduce without the aid of a host cell and don't use the typical cell- division approach to replication.