Talk:Virus/FAQ
 | Below are answers to frequently asked questions about the corresponding page Virus. They address concerns, questions, and misconceptions which have repeatedly arisen on the talk page. Please update this material when needed. |
Q1: Are viruses alive?
A1: Opinions differ on whether viruses are a form of life, or organic structures that interact with living organisms. They have been described as "organisms at the edge of life",[1] since they resemble organisms in that they possess genes and evolve by natural selection,[2] and reproduce by creating multiple copies of themselves through self-assembly. However, although they have genes, they do not have a cellular structure, which is often seen as the basic unit of life. Additionally, viruses do not have their own metabolism, and require a host cell to make new products. They therefore cannot reproduce outside a host cell (although bacterial species such as rickettsia and chlamydia are considered living organisms despite the same limitation). Accepted forms of life use cell division to reproduce, whereas viruses spontaneously assemble within cells, which is analogous to the autonomous growth of crystals. Virus self-assembly within host cells has implications for the study of the origin of life, as it lends further credence to the hypothesis that life could have started as self-assembling organic molecules.[3]
- ^ Rybicki EP (1990) "The classification of organisms at the edge of life, or problems with virus systematics." S Aft J Sci 86:182–186
- ^ Holmes EC (October 2007). "Viral evolution in the genomic age". PLoS Biol. 5 (10): e278. doi:10.1371/journal.pbio.0050278. PMC 1994994. PMID 17914905. Retrieved 2008-09-13.
{{cite journal}}: CS1 maint: unflagged free DOI (link) - ^ Koonin EV, Senkevich TG, Dolja VV (2006). "The ancient Virus World and evolution of cells". Biol. Direct. 1: 29. doi:10.1186/1745-6150-1-29. PMC 1594570. PMID 16984643. Retrieved 2008-09-14.
{{cite journal}}: CS1 maint: unflagged free DOI (link)