AP BIOLOGY

Detailed explanation-1: -To begin transcribing a gene, RNA polymerase binds to the DNA of the gene at a region called the promoter.

Detailed explanation-2: -A promoter is a short region of DNA (100–1, 000 bp) where transcription of a gene by RNA polymerase begins. It is typically located directly upstream or at the 5′ end of the transcription initiation site.

Detailed explanation-3: -Many eukaryotic genes have a conserved promoter sequence called the TATA box, located 25 to 35 base pairs upstream of the transcription start site. Transcription factors bind to the TATA box and initiate the formation of the RNA polymerase transcription complex, which promotes transcription.

Detailed explanation-4: -Many eukaryotic promoters, contain a TATA box (sequence TATAAA), which in turn binds a TATA binding protein which assists in the formation of the RNA polymerase transcriptional complex. The TATA box typically lies very close to the transcriptional start site (often within 50 bases).

Detailed explanation-5: -There are differences in initiation between prokaryotes and eukaryotes. There are different promoters each polymerase binds to. Prokaryotes bind to two promoters, one at the-10 position (the Pribnow box) and one at the-35 position. The eukaryotes bind at the-25 position, also known as the TATA box.