E.coli cells with a mutated $Z$ gene of the lac operon cannot grow in medium containing only lactose as the source energy because
In the presence of glucose, E.coli cells do not utilize lactose
They cannot transport lactose from the medium into the cell
The lac operon is constitutively active in these cells
They cannot synthesize functional betagalactosidase
Define an operon, giving an example, explain an Inducible operon.
A low level of expression of lac operon occurs at all the time. Can you explain the logic behind this phenomena.
In the lac operon, the structural genes are switched off when
In Operon concept, the regulator gene regulates chemical reactions in the cell by