Transcription
A level of regulation, demonstrated by the termination of transcription if tryptophan is abundant, by the tryptophan operon in E.coli cells is called

activation
attenuation
desiccation
corepression

ANSWER DOWNLOAD EXAMIANS APP

Transcription
The sigma factor

recognizes the promotor
provides the catalytic function of cleaving off pyrophosphates during mRNA synthesis
is responsible for recognizing the termination sequence
accomplishes DNA restriction

ANSWER DOWNLOAD EXAMIANS APP