Question Soluion on “Are Viruses Alive?”

Are Viruses Alive?

The term ‘virus’ comes from the Latin word for poisonous, virulentus.  The nucleic acids and proteins that viruses have are similar to those found in living organisms [2]. They exist in the form of virions. After contaminating a host cell, the virus genome is replicated producing viral proteins and this is how is multiplies itself [1]. Initially, viruses were classified as living organisms as they spread from one person to another in the form of diseases like foot and mouth, etc. They were then considered to be smaller form of bacteria and the simplest of all the living beings [2]. But over the years there has been considerable debate in the scientific community over whether viruses are indeed living organisms. Owing to their nature as objects living at the boundary between living and non-living, the origin of virus has always been a topic of debate. There are two opinions on virus “virus early” and “virus late” [3]. “Virus early” proposes that the origin of virus took place before modern cells’ origin. On the other hand “virus late” proposes that the origin of virus took place due to a sudden decreased evolution from cellular forms and all the “cellular paraphernalia” (not required for parasitic form) was lost. Hence whether a virus is to be considered as living or not has always been a confusing issue. Even though capable of evolving, viruses are mostly categorized and considered non-living since they have an acellular structure and are deprived of metabolism [2]. But their ability to multiply in the favorable environment categorizes them to be in the living realm too.

 

References:

[1] Scientific American 2008, Are Viruses Alive?  Viewed 7 March 2015, http://www.scientificamerican.com/article/are-viruses-alive-2004/.

[2] Ladiges, Pauline Y 2000, Biology: an Australian Focus, McGraw Hill, Australia.

[3] Moreira, D & Armanet, CB 2008, ‘Giant viruses, giant chimeras: The multiple evolutionary histories of Mimivirus genes’ BMC Evolutionary Biology journal.

Available from: http://www.biomedcentral.com/1471-2148/8/12.