Repressible Genes are Usually Actively Transcribed When

Question

Repressible genes are usually actively transcribed when:
A) repressor molecules bind to the promoter
B) the end product of the enzymes encoded by these genes is low
C) tryptophan accumulates in the cell
D) quantities of precursor materials are high
E) there is no other substrate that can be used by the cell

Accepted Answer

Repressible genes are typically involved in anabolic pathways and are actively transcribed when the end product of the pathway is low, as the cell needs to produce more of the end product.