The promoter site on the gene is where polymerase is attached while repressor proteins are attached to the site next to it.  
Whether this process is repressible or inducible is determined by whether the product or reactant is the regulatory metabolite.  Its components include two attachment sites located between the regulatory gene and the structural gene.  The promoter site on the gene is where polymerase is attached while repressor proteins are attached to the site next to it.  FTP, name this theory proposed by Jacob and Monod, used to explain how cells control the production of enzymes.
Whether this process is repressible or inducible is determined by whether the product or reactant is the regulatory metabolite.  
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