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Viruses alive in period of finding host?

  1. Jan 23, 2015 #1
    It is known that viruses arent alive. They need a host to replicate. My question is, if they need a host to replicate and stay present in the world, how can be present in the period they don't have a host to begin with? And how long can this period last, forever? It's becoming interesting for me since I read (here) that our DNA consist partly of viruses.
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  3. Jan 23, 2015 #2


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    As I understand it, viruses don't have any metabolic process and thus never have any need for "food" to stay alive. Their only purpose seems to be making more of themselves and for that they do need a host to infect, but being in the host isn't what keeps them alive it just allows them to reproduce.

    It IS an interesting question whether they die of old age or what. I know that there are chemical processes that will kill them inside a host but outside a host I don't know.
  4. Jan 24, 2015 #3
    Interesting question... I would not be surprised if not all that much is known about this.

    Anyway, my guess is that even if virions degrade quickly (for example because of UV-light), the sheer number of viral particles released is enough to ensure that at least some will encounter a new host to infect before being damaged beyond functioning.
  5. Jan 24, 2015 #4
  6. Jan 24, 2015 #5
    What I don't understand is why would a virus want or need to reproduce itself? And what thrives it(s attraction to a host) if a virus is not able to think?

    You wrote "It IS an interesting question whether they die of old age or what".
    I read that also bacteria, like viruses, don't age, but somewhere else I read that they DO age?
  7. Jan 24, 2015 #6


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    How is that any different than "why would a human want or need to reproduce itself" ?

    The fundamental purpose of all life is to reproduce itself just as the fundamental purpose of a politician holding office is to keep holding office.
  8. Jan 24, 2015 #7
    Because of the sex itself, the drug-like feeling
  9. Jan 24, 2015 #8
    ...because a virus couldn't possibly experience pleasure, could it?
  10. Jan 24, 2015 #9


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    This is no different than asking why would wood want or need to burn if heated up in the presence of oxygen. Or why would water want to freeze into snowflakes.
    If the conditions are right for it to happen, a process will happen.
  11. Jan 25, 2015 #10


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    In general in biology, things exist because they reproduce themselves. If things don't reproduce, they go extinct and don't exist anymore.
  12. Jan 25, 2015 #11


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    We don't know whether pleasure is actually part of the mechanism of action for animals; it could just be a spandrel. Further, the neural correlates of pleasure in humans and mammals are hard to transpose to even other mammals with less cortex, let alone the nerve bundles of insects or the molecular pathways of viruses.
  13. Jan 27, 2015 #12
    While Viruses aren't "alive," they are organized structures. In physics, organization requires energy to maintain its structure or it breaks down over time, this is called entropy. Viruses, while not alive, do "die," when introduced to bleach or the correct conditions. These conditions vary from virus to viruses are there are viruses that can survive outside of a host. Also since viruses do break apart over time, more or less quickly depending on the conditions, if they do not find a host/the correct conditions to replicate, they disappear, thus needing to reproduce to continue to exist. I think my response is mostly accurate, I hope it helped.
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