Answer:
The correct order would be:
RNA polymerase unzips the DNA molecule.
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Free RNA nucleotides pair with the complementary DNA nucleotides on one strand of DNA.
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The mRNA molecule breaks away as the DNA strands rejoin.
Transcription is the process by which nucleotide sequence of the DNA is decoded in the from the nucleotide sequence of RNA.
It is the first step of gene expression which is catalyzed by DNA dependent-RNA polymerase.
The process of transcription can be divided into three steps:
1. Initiation: RNA polymerase binds to the promoter region of the DNA and forms the transcription bubble with the help of transcription factors.
2. Elongation: RNA polymerase adds RNA nucleotides complementary to the nucleotide sequence of the template strand of DNA.
3. Termination: Once the RNA polymerase reaches the terminator region of the DNA, nascent RNA chain and RNA polymerase fall off with the help of termination factors. The transcription bubble is sealed back by rejoining of the DNA strands.
