What is life?

1. 60

   janesixposted 10 years ago

   What are the components of a living organism compared to a nonliving one? Is there any specific thing(or things) that a thing must have in order to be considered living?
   
   Self-movement
   Self-replication
   Born-Growth-Reproduction-Death cycle (does a thing HAVE to die?)
   URGE to reproduce and survive (instincts)
   
   Is there a "spark of life" or is that not something that's necessary?
   
   How about crystals? Are they alive?
   
   "But what is to say that a crystal does not do all of these things? That crystals grow, and sometimes parts of them break off and become new growing crystals suggest that they not only gain sustenance from the earth for growth, but can reproduce. That they do this while in their natural environment in the earth suggests that they surely interact with their surroundings." http://perdurabo10.tripod.com/storagej/id72.html
   
   (This article is unscientific, I will try to find something else more credible on crystals)

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2. 60

   janesixposted 10 years ago

   1.Homeostasis: Regulation of the internal environment to maintain a constant state; for example, electrolyte concentration or sweating to reduce temperature.
   2.Organization: Being structurally composed of one or more cells — the basic units of life.
   3.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.
   4.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.
   5.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.
   6.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.
   7.Reproduction: The ability to produce new individual organisms, either asexually from a single parent organism, or sexually from two parent organisms.
   wikipedia

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3. 60

   janesixposted 10 years ago

   I'm going to list things that non-living things can do in relation to these things, to see if there are any that solely involve living things.
   
   
   1.Homeostasis: Regulation of the internal environment to maintain a constant state; for example, electrolyte concentration or sweating to reduce temperature.
   
   A well designed house, a termite hill, a beehive, anthill
   
   2.Organization: Being structurally composed of one or more cells — the basic units of life.
   
   A beehive(does it have to have a neucleus? DNA?
   
   3.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.
   
   ?
   
   4.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.
   
   Crystals, sediment layer
   
   5.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.
   
   A mountain, a river
   
   6.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.
   
   iron to a magnetic source
   
   
   7.Reproduction: The ability to produce new individual organisms, either asexually from a single parent organism, or sexually from two parent organisms.
   
   crystal

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4. 60

   janesixposted 10 years ago

   Is life just something that has DNA?

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      Kathryn L Hillposted 10 years agoin reply to this

      Stimulus is what scientists try to observe. I think amoebas are stimulated to follow light….

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         janesixposted 10 years agoin reply to this

         I don't know anything about amoebas. I assume they have dna, they eat, defacate, reproduce, die. They must get hungry, or they wouldn't eat. Why do they do that, if they don't have a brain(which is what supposedly our "instincts" are, chemical reactions in the brain. )

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         1. 76

            Kathryn L Hillposted 10 years agoin reply to this

            One time you said we need to learn what the laws of nature are. Apparently there was a movement to throw us off the track of knowing the laws of nature… as though there weren't any. I believe nature has laws and that we do need to become conscious of them. What are you trying to discover? Thomas Aquinas wrote of the laws of nature. Have you read anything by him?

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            1. 60

               janesixposted 10 years agoin reply to this

               We do need to learnt he laws of nature. I think we will someday. It won't be by me probably though, I won't go near that rabbit hole anymore.
               
               I only have one contribution to society. A small math trick that probably serves no purpose anyway, and I don't know enough math to turn it into a formula.

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                  Kathryn L Hillposted 10 years agoin reply to this

                  Well, that is impressive!

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                     janesixposted 10 years agoin reply to this

                     lol..not really!

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                        Kathryn L Hillposted 10 years agoin reply to this

                        maybe not to you, but to me. No arguing that.
                        Why? Because you called it a contribution to society. Its the thought that counts.

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5. 60

   janesixposted 10 years ago

   A prokaryote (a form of bacteria) is the simplist form of life. It is basically a shell for it's own dna. But it is alive, it functions as a living being. It socializes, forms communities, and communicates with others of it's species. It has no brain. No nerves. Can it feel things? Does it have instincts? What makes it "want" to reproduce or eat? Does it want to? And if not, then why does it do those things at all?

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6. 60

   janesixposted 10 years ago

   Did DNA form first, and then somehow made protection around itself (the cell?)

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      calculus-geometryposted 10 years agoin reply to this

      This covers the evolution of various cell structures from the primordial soup.
      http://www.ncbi.nlm.nih.gov/books/NBK9841/
      
      and more about the earliest self-replicating molecules
      
      http://evolution.berkeley.edu/evosite/e … igin.shtml

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      1. 60

         janesixposted 10 years agoin reply to this

         Thanks! That's what I was looking for.
         
         I was almost right, except it was probably RNA that learned to self-replicate,and then formed the cell membrane around itself.

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7. 60

   janesixposted 10 years ago

   DNA hasn't changed since life began (so they say, although I have no idea how they could know that.)

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8. 95

   wildernessposted 10 years ago

   A tough question, and one I can't answer and can't point to anyone that can.
   
   About all I CAN say is that death is not a part of life - any organism that reproduces by twinning itself (an amoeba) may live forever.  If one of them dies, was it the original or a twin?

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      janesixposted 10 years agoin reply to this

      Plus there are trees that live for thousands of years. And animals that don't reproduce, although they are obviously alive (like a mule).

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         wildernessposted 10 years agoin reply to this

         One must wonder as well - will we one day create machine life?  Life, without organic cells?  We already create computers/machines that reproduce themselves, making more computers/machines...

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            janesixposted 10 years agoin reply to this

            Von Neuman machines.....creepy.

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               wildernessposted 10 years agoin reply to this

               I, Robot.  Perhaps Asimov was a real prophet, seeing our future and reporting on it the best way he knew how.

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9. 76

   Kathryn L Hillposted 10 years ago

   But, we must remember, humans are not automatons and robots/machines will never love.

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