not cells, dependent on their cellular hosts, metabolically inert outside of a susceptible cell; "fluid poison"
a virus that cannot replicate because it lacks a full complement of viral genes; replication occurs in mixed infections with a helper virus
during replication in co-infected cells, the genome of one virus may become encapsidated in the heterolgous protein coat encoded by the second virus
during viral replication, the capsid sometimes encloses the host nucleic acid rather than viral nucleic acid, such particles look like ordinary virus particles when observed by electron microscope, but do not replicate
viral DNA that is integrated into host cell chromosome in a latent state and must be activated before it is transcribed, leading to production of progeny virions
responsible for structural symmetry of the virus particle, protects, facilitates attachment, some contain enzymes which play roles in the infection process, also determines the antigenic characteristics of the virus
the genome of all DNA viruses of vertebrates is ____________ (all viral genes contained in a single chromosome).