Nov 16, 2015 · Lac operon is an inducible system , it remains generally in off state , but in presence of Lactose it is switched on So Presence or absence of Lactose regulates operon functioning

Nov 17, 2017 · A great example I know is the lac operon located in prokaryotic DNA that dictates whether bacteria in the lower GI tract use lactose or glucose for energy. The lacI area of the DNA constitutively expresses a repressor molecule that negatively controls lacZ and lacY expression by blocking RNA primase from synthesizing RNA in order to break down galactose. When there is high levels of ...

Jul 16, 2017 · trp operon is regulated in completely different way compared to lac operon though both are described under gene regulation in cells of prokaryotic organisms like E.coli. trp operon is a 'repressible' operon with negative regulation of gene expression.