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                             A 
            large molecule composed of one or more chains of amino acids in a 
            specific order; the order is determined by the base sequence of nucleotides 
            in the gene that codes for the protein. Proteins are required for 
            the structure, function, and regulation of the body's cells, tissues, 
            and organs; and each protein has unique functions. Examples are hormones, 
            enzymes, and antibodies.  | 
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