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How do genes command things?

  1. Jan 9, 2005 #1
    What chemical reactions take place when genes "tell" cells what to do? I'll have more specific questions later but this will be a decent start.
  2. jcsd
  3. Jan 9, 2005 #2
    A gene is a sequence of DNA, a protein is a sequence of amino acids. The sequence of the first determines the sequence of the second.

    The sequence of amino acids determines the protein's shape and function. Some are colors in your iris, some are hormones, some are enzymes which favor certain reactions.
  4. Jan 10, 2005 #3


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    Genes are like a book of words, each word has a different meaning. But each word need to be processed in order to become active.

    Genes are read by certain cellular machineries, this process is called transcription: DNA is read and an mRNA copy (this is a messenger molecule) is made. Then after transcription, translation takes place. This is the process where the mRNA is translated into a protein.

    Proteins have very specific functions in a cell, they can be enzymes, transcription factors, receptors, etc.
  5. Jan 13, 2005 #4
    and these proteins are the actual muscle that make commands into actual transformations/adaptations? Or are they another form of a messenger?
  6. Jan 13, 2005 #5


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    It stops there. Proteins help make up most of the human body
    Once you go protein you can't go back. :wink:
  7. Jan 22, 2005 #6
    There's also differential transcription and translation in some cells versus others. For example, the lens cell in the eye contains thousands of crystallin proteins which serve to focus light (I think). In the growing lens cells, there would be very high amounts of transcription of the crystallin message, and translation of the protein.

    In contrast, blood cells would not have transcription and translation of crystallin, but instead have transcription and translation of haemoglobin.

    In my opinion, it is not genes that "tell" what cells can do. Instead, it is the transcription of certain genes that limit the abilities of the cell. There are many things that determine what a cell's ability should be, and should include, for example inducing factors from the surrounding connective tissue. Theoretically, if a cell were to be located in some other place of the body, it would change its transcription activities accordingly to what its new destined function is.

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