Question

which action is one role of rna polymerase during transcription?
○ to break down an already existing protein
○ to switch uracil with thymine on the exposed gene
○ to produce a start sequence
○ to build a molecule of mrna

Explanation:

RNA polymerase is an enzyme that plays a crucial role in transcription. Transcription is the process of synthesizing RNA from a DNA template. During transcription, RNA polymerase binds to the DNA at a specific region called the promoter. It then unwinds the DNA double helix and uses one strand of DNA as a template to synthesize a complementary RNA molecule. In the case of mRNA (messenger RNA) synthesis, RNA polymerase builds the mRNA molecule by adding nucleotides that are complementary to the DNA template strand.

• Breaking down an already existing protein is not a role of RNA polymerase. Proteins are broken down by proteases.
• Uracil is present in RNA, and thymine is present in DNA. RNA polymerase does not switch uracil with thymine. Instead, it incorporates uracil into the RNA strand when the DNA template has an adenine.
• The start sequence (promoter) is recognized by RNA polymerase, but it does not produce the start sequence. The start sequence is part of the DNA.

Answer:

to build a molecule of mRNA