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How many chemicals are people made from?

  1. May 2, 2005 #1
    How many different molecules are people made from?
    Are there lots of new molecules to be discovered
    and if so,how is this known?
     
  2. jcsd
  3. May 2, 2005 #2

    DaveC426913

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    Uncountably many. Even proteins (which are extremely large and complex molecules) there are many many different molecules.

    Asking if there are any new molceules to be discoved is equivalent to asking if there are any new ways to assemble Lego if you have an unlimited supply of the 92 types of blocks available.



    Unless you said molecules when you meant atoms.
    1] There are a small number of atoms (between 92 and 117, depending on what you want to do with them)
    2] humans are made of a handful of these
    3] We have discovered all naturally occurring atoms, but are creating more as we go (they are unstable and last for a very short time)
     
  4. May 2, 2005 #3

    Monique

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    There are 20 proteins used to build amino acids, these can occur in any sequence and of any length. Besides proteins there are other molecules like sugars or fatty acids, so there are many molecules that can be made.
     
  5. May 2, 2005 #4

    DocToxyn

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    I think you meant to say "there are 20 amino acids used to build proteins". :biggrin:
     
  6. May 2, 2005 #5

    Monique

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    whoops! :blushing:
     
  7. May 2, 2005 #6
    I see someone counted their lego... :rolleyes:
     
  8. May 2, 2005 #7

    JamesU

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    Are'nt there more than 92 types? Or are you not including the bodies and movie ripp-off legos?
     
  9. May 2, 2005 #8

    DaveC426913

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    :)

    No, the lego is an analogy to atomic elements. There are 92 stable elements with which to build molecules.

    Asking how many molecules are yet to be discovered is equivalent to asking how many unique constructions you can make out of Lego - pretty much infinite!
     
  10. May 2, 2005 #9

    JamesU

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    Oh. thank god you're not one of those lego collecters that waste their salary on plastic.. :biggrin:
     
  11. May 3, 2005 #10
    But surely there is a limit to the size of molecules in a cell?
    And very large molecules would be prone to errors when
    they are made- there must be a limit to molecule size,
    even outside cells?
     
  12. May 3, 2005 #11

    DaveC426913

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    Funny you should ask. Our cells contain one of the largest and most complex molecules in the known universe. Can you guess what it is? :biggrin:

    I did not know this but, according to Wikipedia, in humans, it can be as long as 5 centimeters! (That's a 5cm long molecule folks.)
     
  13. May 5, 2005 #12
    You're talking about that deoxyribonucleic acid stuff right? Or is it ribonucleic acid you mean to have us guess? Another perhaps? :smile:
     
  14. May 6, 2005 #13

    JamesU

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    yeah, and it's deoxyribonucleic acid(DNA)
     
  15. May 14, 2005 #14
    Even if molecules were limited in size there would e a HUGE number. My plant biology professor gave us this example: There are 61 common monosaccharides living things use, and 4 ways they can attach to each other. If polysaccharide chains always had to consist of exactly 100 monosaccharides, there would still be (61 times 4)^100 possible polysaccharides. So living things have more possibilities for molecules than they could ever use, and chemicals are being created all the time through mutations.
     
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