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?
Exactly the same question I had. I will definitely research further and get back to you on this, but a very good question. It is known that active viruses can reside on certain substances such as water vapour for a short amount of time, but the real question is, by what means do dormant (Inactive) viruses exist? For instance, how do certain viruses make a comeback after many years, without having a host all that time to duplicate in? How did their protein-based capsid protect their Nucleic Acid all those years without a means of replication? Where did the virus reside, if not in a host? These are very good questions to consider. I would hypothesize that the virus survives by residing in an endospore-like state, however that would not be logical, as in order to accomplish such a change in structure, the virus would need some sort of ribosome-like organelles to read the genes necessary in making a protective casing. While I can sit and ponder the possible ways in which a virus may strengthen its capsid to preserve its Nucleic Acid, I would just be taking simple "Shots in the dark" if you will, so I suppose I will do additional research and get back to you on the matter. Once again, bravo on the question, I had the same one on my mind.
The definition of life, has certain conditions, such as the ability to replicate. A virus does not meet this particular condition of life, all by itself. Rather it needs a host to serve as a surrogate for reproduction. If we extrapolate this condition of life, to a woman who cannot have a baby, but has viable eggs, she is not alive, as whole, using the replication condition. She is alive at the cellular level, but she is not alive as a multicellular unit. This shows the definition of life is flawed as we scale up. One may need to harvest her eggs and use a surrogate mother, then she will be considered, alive. She falls under the definition of a virus. The same can be true of males. He may not be able to reproduce for various reasons and therefore is not alive except at the cell level. Under certain conditions he may not be able to reproduce, due to his mate not being fertile. She is not the proper host for him to be alive. I poking fun to show the flaw in the definition of life. A virus is different in that it exists at the microscopic level and therefore comes under the cell size umbrella. It is not multicellular ,where the definition breaks down. As a unit, the virus has the potential to reproduce using a surrogate; can come alive. Instead of multicellular, it is multi-layered, with all the layers defining its unit nature. A priest and a nun are not alive based on choice not to reproduce. Metabolism and growth alone are not enough according to the definition of life. The ancients seemed to understand the bias of natural traditions, and found a loophole into non-material life that allowed the body whole to be dead, while something else remains alive that does not fit into the definition of the macro-forms life; soul and spirit.
My nonbiologist view point on this is that viruses are alive. The reason I say that is that they can reproduce and they are organic (contain DNA or RNA). When a virus is not in a host it has a certain amount of time that it can survive. For instance we know that measels virus survives for quite a while in the air. Measel viruses will not last a week outside the body, in other words they die after a certain amount of time outside the host. If they die then they must have been alive. Like I said that is a sort of brute force nonbiologist view point. [shrug]
Being alive is very questionable thing.. Soul?.. Do you think atoms and subatom particals are alive also? They always try to have some chemical or physical interactions.. Whats nucleic acids? A bunch or carbon based molecules.. At what part being alive comes?
A soul appears to just be something made up by various religions. Do you think bacteria have souls? No. Do you? They do? I don't think atoms or subatomic particles try to do anything. Answer Like CO2? What about it? That is what is being discussed here. What do you think?
Yes i do based on how you define soul concept. Imagine hardware and software, if you think bacteria physical structure as an hardware why not to have a software running it ? Possible..It is again based on how you define being alive. Tell me your definition and let me tell you if i do or not Really ? Then why they just dont stay steady ? It can start wherever you define, nucleic acids just some common idea.Lets define nucleic acids as coding material but do you think they means any kind of being alive evidence does it need a software ? If you bring proper conditions you can produce nucleotides, i hope in near future we see some solid results of producing nucleic acids and see whats gonna happen when these artificial ones placed into capsule Please Register or Log in to view the hidden image!
The (loose) consensus of biologists is that a thing must have most of these attributes (as listed in Wikipedia) to be defined as "alive": Homeostasis: Regulation of the internal environment to maintain a constant state; for example, electrolyte concentration or sweating to reduce temperature. Organization: Being structurally composed of one or more cells—the basic units of life. Metabolism: Transformation of energy by converting chemicals and energy into cellular components (anabolism) and decomposing organic matter (catabolism). Living things require energy to maintain internal organization (homeostasis) and to produce the other phenomena associated with life. Growth: Maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size in all of its parts, rather than simply accumulating matter. Adaptation: The ability to change over time in response to the environment. This ability is fundamental to the process of evolution and is determined by the organism's heredity, diet, and external factors. Response to stimuli: A response can take many forms, from the contraction of a unicellular organism to external chemicals, to complex reactions involving all the senses of multicellular organisms. A response is often expressed by motion; for example, the leaves of a plant turning toward the sun (phototropism), and chemotaxis. Reproduction: The ability to produce new individual organisms, either asexually from a single parent organism, or sexually from two parent organisms. or "with an error rate below the sustainability threshold." Obviously, the weakness in this paradigm is that it only describes life on one single planet: Earth. We have no idea what we'll encounter on other planets. But the notion that only most of these attributes are required is a nod to the expectation that we will eventually find them. It's quite possible that when humans finally land on a planet with an environment that can support life, they may walk right past the creatures without even realizing that they're alive.
