The cells of the immune system function to combat viruses in two ways: B cells secrete antibodies which neutralize the virus (humoral immunity) and T cells recognize and kill infected cells (cell-mediated immunity) In addition, interferon activity is very effective. Just a few molecules of interferon bound to the surface of a cell can protect [...]

Icosahedral RNA Viruses Enveloped SS Togaviridae Flaviviridae Retroviridae Non-Enveloped SS Picornaviridae Caliciviridae Non-Enveloped DS Retroviridae Helical RNA Viruses Helic RNA viruses are SS (minus sense) Orthomyxovirus Influenza Paramyxoviridae Parainfluenza virus Measles virus Mumps virus Respiratory syncytial virus Rhabdoviridae Rabies virus Bunyaviridae LaCrosse virus Hantann virus Arenaviridae Lassa virus Coronaviridae Retroviridae Filovirus Marbug virus Ebola virus [...]

Small, infectious, obligate intracellular nonliving molecular parasite. Have ss or ds genome of DNA or RNA. Multiplication requires host cell. Progeny are the vehicle of transmission of virus. Icosohedral virus (simple/complex) and helical virus. Spindle viruses are specific to archaea. (+) RNA = mRNA; (-) RNA = complimentary mRNA. Viruses are filterable & passageable. Envelope [...]