lunes, 18 de marzo de 2013

Are viruses actual living creatures ?

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A newly discovered virus has reignited the debate over the classification of viruses as living creatures. In order to qualify as a "living creature" the organism must have a genome, be able to grow, replicate and to evolve by adapting to its environment over successive generations. Viruses are generally considered to be primitive particles of DNA and do not meet these criteria, but new research in to a virus that can steal its host's immune system has turned this idea on its head.
Humans and other living creatures possess an adaptive immune system, capable of developing defenses and passing these down to successive generations of cells. The discovery of such a system present in a virus has greyed the area between "biological entity" and "living creature" and is likely to fuel further debate on the subject for years to come. For a long time, scientists have deemed viruses, which are little packages of infective material that can only replicate inside living organisms, to be primitive particles of DNA and RNA, termed a “biological entity. ” Thus, not living.

source and credit a unexplained-mysteries