Certain type of virus exists in several forms of stages. The free virus particle, or virion, consists of a molecule of nucleic acid, either DNA or RNA, depending on the specific virus, surrounded by protein and in some viruses, also lipid and carbohydrate. The virion is inert, because its lacks many of the components that are necessary for independent life and reproduction; it does, however, provide for the transfer of the nucleic acid from host cell to host cell. Replication can occur only when the nucleic acid enters a host cell. Within the cell, the nucleic acid functions as genetic material and directs the synthesis of proteins. This results in the production of new virions, which then are released from the cell and can initiate new cycles of infection.
More detail of Virus Characteristic
