Are Viruses Considered As 'alive' Following up on the robots-life issue

[Haydn 0]

yeah,viruses r considered as 'alive'. if nt,how can they cause so much troubles 2 us? n if nt,how can theya ct on heir own,attacking us??

[iGuest 3]

i feel abit dumb asking this but what the heck are you on about with all of this stuff i was like okay :S here it is heres you see, the viron (name of one virus molecule) actually 'lands' on this great 'orb' which represents a cell in your body. I'll guide you through the process.1. This is the evul viron, seeking a good host. No, not a site-hosting company . A host is a living organism in which a parasite (such as a virus) can live, and eat from.2. The ship has landed. The virus now clamps it's little clawlike tentacles into little tentacles on the outside of your cell to get a good grip for the next phase.3. In this phase the viron pushes itself through the membrane of the cell with brute force, and injects it's DNA into your cell (a viron can also contain only RNA, but for the sake of simplicity, we'll keep to DNA). Notice that the other viron, the on the right, just uses a sort of needle. 4-5. The DNA reaches the core of the cell and infiltrates it. In this core lies the most important part of the cell: your DNA. The viron's DNA pushes itself between yours and assumes control over the cell. It starts redirecting everything in the cell: it orders the cell to make new virons. Many new virons. 6. After a while, there is no space left for the new virons to go, but they keep coming, so eventually, the cell bursts open, and the young virons are cast out into the cruel world to go find a new host.Not a nice scene now is it? Next: the symptoms of life. If a supposed organism shows these signs, it's alive. So they say. These 7 signs are as follows:Theme #1 - CellsFrom Dictionary.com:Biology. The smallest structural unit of an organism that is capable of independent functioning, consisting of one or more nuclei, cytoplasm, and various organelles, all surrounded by a semipermeable cell membrane.Here we come across the first flaw. It says: ...capable of independent functioning... which is not the case with a virus. He has to use a host-cell in order to do things like a normal cell.Theme#2 - OrganizationThis means to say that living organisms have a basic structure. Like an energy provider, a command centre, etc.This is partly true with a viron. They have a nuclei (the core, containing DNA), but nothing else. So there is only a commando centre. So well, they are organised, as one big structure. Theme#3 - Energy Use'Living matter acquires matter and energy from the external environment and converts it into different forms.'ripped from Oceans Online.Well, this certainly is a DON'T. That exactly why viruses need hostcells, they can't make energy for themselves.Theme#4 - Homeostasis'Living matter maintains some type of homeostasis.'This one is universally accepted. Homeostasis is the property of an open system, especially living organisms, to regulate its internal environment so as to maintain a stable condition. Well, this one we can also cross out on our list. As a matter of fact, a viron has a very minimalistic internal environment.Theme#5 - GrowthDoes a virus grow? Well, if you see a car being built -piece by piece is being put on- and consider that the 'growth' of the car to adulthood, then yes, a viron can grow. But as I see it virons are mainly assembled.Theme#6 - Reproduction'Living matter reproduces and passes on genetic material as a blueprint for growth and subsequent reproduction'Well these babies produce allright. They produce so well we are being killed in the process. Theme#7 - Evolution'Living matter evolves.'Yes, a virus can evolve. Look at the recent 'SARS'. Or influenza, to stay closer at home (influenza = flu, your average home-garden-kitchen virus). SARS originally only affected pigs and animals of the like, until it evolved slightly and could acces humans. And Influenza shows signs that they are becoming more and more resistant to anibiotics, the big medicine that stopped great influenza epidemics. So yes, a virus can certainly evolve.Lacking 4 of the 7 needed signs, I'd say that it is not really alive. But then again, the most important of these characteristics of life are containing DNA and evolving, in which viruses excellently succeed.If I had to put it in my own words: Virons are like zombies are to men. Not with a free will, not with the capability to make food for itself, and needing a host (like a human) to survive, but still with the few vital signs of life.NOTE: zombies need to eat human flesh in order to 'stay alive'. (Never really figured out why )Terms:Viron: A microscopic object consisting out of an outer membrane, an inner membrane and a core with DNA/RNAVirus: A collective noun for a specific group of virons.DNA: A long spiralled string of specific proteins that is the blueprint of your body. It describes exactly how you look and what kind of curve your nose has. It is in every cell of your body. If you could take one DNA-string out of a cell and stretch it out, it would be around 2 metres in length (6.6 feet). Surprising, no ?RNA: Similar to DNA, but not quite the same. It is also a a string of proteins, but one of the main functions of RNA is to copy genetic information from DNA and then translate it into proteins. In virons it is like a copy of DNA that never existed. URLS:Physics forumWikipediaAnd some other site I couldn't remember Hope this makes maybe somewhat clearer, plenty to debate still!Qop

[Merovingian 0]

Does anyone have any thoughts on prion diseases e.g. vCJD I haven't read through all of these posts but I do have a degree in biology and have studied Microbiology while at university. Maybe we should not concern ourselves with comparing a virus to higher organisms just yet, as they are considerably different. Is a prion disease live or dead? Is a virus similar to a prion and would you consider a prion dead and a virus to be alive? Are these just intermediary phases of their evolution, which could lead onto further developments and eventually, a 'living being'? Let me know what you think.

[iGuest 3]

In my opinion, I do not think that viruses are alive. They lack a few properties of life such as homeostasis, they do not gorw, and they do not metabolize. Since these are part of the properties of life, I don't think that they are alive.

-reply by Phillby

[iGuest 3]

Viruses are both, dead AND alive. Outside aLiving cell they are nothing but a large complex of organic chemicals.Inside the cell they assume some properties of life. I believe it'sImpossible to truly create life from inert matter, without usingAnother life form to assist in the process. Or at least we are a veryLong way from it. Since it is now fairly easy to create certain viruses fromScratch, as done by Eckard Wimmer of Stony Brook University, I thinkIt's not really life that's being created, but rather at best"re-created" from known information. This life can be "molded" withinCertain parameters to be put to good use, for instance in the making ofNew vaccines, as the groups around Eckard Wimmer and Steffen MuellerSubsequently showed (some explanation found here: http://forums.xisto.com/no_longer_exists/ The closest thing to creating some type of new life form is theGroup around Craig Venter. They use a completely synthetic bacterialGenome, and try to transplant it into an empty bacterium, which had itsGenome completely taken out. However, as I said this process depends onAn empty surrogate bacterium, which contains all the "stuff of life" inForm of thousands of different proteins, EXCEPT the information (I.EGenome) to replicate itself. So, even if they succeed in doing that, itMay new life form, and after "booting" it from the synthetic genome, itWill assume the properties encoded by the new genome, but it firstNeeded that "empty" bacterial shell, and THAT perhaps can never be madeFrom scratch, because it is way too complex.