AP BIOLOGY

Detailed explanation-1: -RNA polymerase is the main enzyme involved in transcription. It generally uses single-strand DNA to synthesize complementary RNA strands.

Detailed explanation-2: -Gene expression is linked to RNA transcription, which cannot happen without RNA polymerase.

Detailed explanation-3: -RNA polymerase (green) synthesizes RNA by following a strand of DNA. RNA polymerase is an enzyme that is responsible for copying a DNA sequence into an RNA sequence, duyring the process of transcription.

Detailed explanation-4: -Transcription is carried out by an enzyme called RNA polymerase and a number of accessory proteins called transcription factors.

Detailed explanation-5: -During transcription, RNA polymerase makes a copy of a gene from the DNA to mRNA as needed. During transcription, the DNA site at which RNA polymerase binds is called as promoter. Transcription commences with one or more sigma factor protein binds to the RNA polymerase holoenzyme, allowing it to bind to promoter DNA.