These entities can have an anti-terminator, such as LicT protein for sacPA, which stabilizes a secondary RNA structure.  Early termination of their processes, which can occur via an alternate loop structure with excess of a particular amino acid, is known as attenuation.  They can be inducible, as by IPTG for a well known example, and they can contain two kinds of repressors: a translational one, and a better understood transcriptional one, which binds to the operator site.  All of them must have these operator sites, a
These entities can have an anti-terminator, such as LicT protein for sacPA, which stabilizes a secondary RNA structure.  Early termination of their processes, which can occur via an alternate loop structure with excess of a particular amino acid, is known as attenuation.  They can be inducible, as by IPTG for a well known example, and they can contain two kinds of repressors: a translational one, and a better understood transcriptional one, which binds to the operator site.  All of them must have these operator sites, as well as promoter sites where RNA Polymerase originally binds.   FTP, name these prokaryotic strips of DNA that regulate expression of related genes, which include the trp [trip] and lac varieties.
These entities can have an anti-terminator, such as LicT protein for sacPA, which stabilizes a secondary RNA structure.  
operons