The nucleotide where RNA polymerase actually begins synthesis of the mRNA.Group of answer choicescodonpromoterA sitestart pointTATA boxintronNext

Break Down the Problem

1. Identify the role of RNA polymerase in mRNA synthesis.
2. Determine the specific region where RNA polymerase binds to initiate transcription.

Relevant Concepts

1. Promoter: A DNA sequence that serves as the initiation site for RNA polymerase.
2. TATA Box: A conserved DNA sequence within the promoter region that is crucial for the binding of RNA polymerase.
3. Start Point: The exact nucleotide location where RNA synthesis starts.

Analysis and Detail

1. Promoter: The promoter serves as the primary binding site for RNA polymerase. This region contains signals that indicate the start of a gene and is essential for the assembly of the transcription machinery.
2. TATA Box: Often found within the promoter, the TATA box is near the transcription start site (the start point) and is recognized by transcription factors, aiding in the recruitment of RNA polymerase.
3. Start Point: Although the start point refers to the specific nucleotide where transcription begins, it is located at the promoter region.

Verify and Summarize

The correct choice among the given options emphasizes the role of the promoter as the site of initiation for mRNA synthesis where RNA polymerase binds.

Final Answer

The correct answer is promoter, as it is the region where RNA polymerase binds to initiate the synthesis of mRNA.