The promoters of positively controlled operons require activator proteins because The promoters of positively controlled operons require activator proteins because they are needed to bind to the allosteric site of RNA polymerase. RNA polymerase easily recognizes the consensus sequence. the promoters bind RNA polymerase weakly and utilize activator proteins to help RNA polymerase recognize the promoter. they are required to inactivate the repressor proteins.

the promoters bind RNA polymerase weakly and utilize activator proteins to help RNA polymerase recognize the promoter.

Explanation:

The promoters of positively controlled operons require activator proteins because the promoters bind RNA polymerase weakly and utilize activator proteins to help RNA polymerase recognize the promoter.

surface mining destroys mountain tops, landscapes, forests and wildlife habitats. on top of that, it leads to soil erosion and destruction of agricultural land. the landscape changes can also disrupt river channels and streams, which leads to flooding. which, can destroy plant life and other animals as well.

explanation:

ι вєℓινє тнє αиѕωєя тσ уσυя qυєѕтισи ιѕ в. ℓуѕσѕσмє

ι нσρє тнαт ι ¢συℓ∂ нєℓρ уσυ.