Final answer:
The claim that promoters are signals in RNA is false; promoters are specific DNA sequences that act as binding sites for RNA polymerase to initiate transcription.
Step-by-step explanation:
The statement that promoters are signals in RNA that indicate to RNA polymerase when to begin transcription is false. Promoters are actually specific DNA sequences located upstream of the transcription start site. They are crucial for the initiation of transcription because they provide the binding site for RNA polymerase and transcription factors, allowing RNA polymerase to position itself near the transcription start site. This is where RNA polymerase starts unwinding the double helix to synthesize new RNA. In prokaryotes, promoters typically have -10 and -35 regions important for polymerase binding, while eukaryotic promoters feature complex elements including the TATA box. The binding of transcription factors to the promoter is essential in eukaryotes to recruit RNA polymerase and initiate the formation of the transcription initiation complex.