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Conservation of Matter

  1. Dec 27, 2009 #1
    Let me first say that I am not a bio person. To be honest, I dont know much bio at all. I have a question regarding cell replication and conservation of matter. How do single cell organisms get the matter to self replicate? When I learned about it in bio it just made it seem like they appeared out of nothing (which obviously violates the laws of physics)!
  2. jcsd
  3. Dec 27, 2009 #2
    Could you clarify what you are asking?
    For most biological specimens, obtaining matter for replication is varied. It is usually done through consumption of other organisms and the environment.
    It depends on what the organism is looking for. For example, some protists will consumer other protists and break down their meals into the matter; moss can sometimes grow on trees implanting their "roots" (i forgot the proper term) in trees for water and nutrients.
    Sometimes the environment limits an organisms ability to gather the material so they will adapt. The venus fly trap has evolved to catch flies because nitrogen is scarce in the bogs where they live. Peanut plants will take in nitrogen in the air and manipulate to nitrite, etc.
    For other organisms, the environment usually circulates nutrients so that they have not developed methods to obtain these materials.
    You are right that it becomes impossible for the cell to replicate without the materials.
  4. Dec 27, 2009 #3
    Like when you see a video of bacteria replicating. You see a couple, then all of a sudden there are hundreds. Where does the matter that is used to create these new bacterium come from?
  5. Dec 27, 2009 #4
    Ah, now i understand.
    Cell replication occurs in steps, in order for replication to occur, the matter must be obtained originally. Now in those videos, the bacteria are usually treated to some agar gel, which has vast amounts of sugar. Bacteria can usually break down the sugar molecules (to form rna and other structures), when they have enough matter, they replicate. Prokaryotic replication is a quick and efficient process overall.
    Is this what you were looking for?
  6. Dec 27, 2009 #5
    Yes. Thank you very much
  7. Dec 28, 2009 #6
    Your question is - given a tiny seed that is planted in the ground and many years later... where on earth did the tree come from!? Surely the mass of a tree is much greater than the mass of the seed! Where did all this solid material come from?

    The simple answer is carbon dioxide from the atmosphere and water, which turns into simple sugars.

    All life has some sort of metabolic process where they'll take resources from their environment and convert it into matter for their own use (and excrete the rest).
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