AP BIOLOGY

Detailed explanation-1: -Transcription Initiation. The first step in transcription is initiation, when the RNA pol binds to the DNA upstream (5′) of the gene at a specialized sequence called a promoter (Figure 2a).

Detailed explanation-2: -RNA polymerase binds to a sequence of DNA called the promoter, found near the beginning of a gene.

Detailed explanation-3: -RNA polymerase is the main transcription enzyme. Transcription begins when RNA polymerase binds to a promoter sequence near the beginning of a gene (directly or through helper proteins). RNA polymerase uses one of the DNA strands (the template strand) as a template to make a new, complementary RNA molecule.

Detailed explanation-4: -RNA polymerase and the necessary transcription factors bind to the promoter sequence and initiate transcription. Promoter sequences define the direction of transcription and indicate which DNA strand will be transcribed; this strand is known as the sense strand.

Detailed explanation-5: -A promoter is a region of DNA where RNA polymerase begins to transcribe a gene. Normally, promoter sequences are typically located directly upstream or at the 5′ end of the transcription initiation site (Lin et al., 2018).