What is the purpose of RNA polymerase?

Question

What is the purpose of RNA polymerase??  
A. To become a protein  
B. To become a nucleotide  
C. To function as an enzyme  
D. To develop into a terminator

Accepted Answer

Correct Answer: (C)To function as an enzyme. 
Rationale: RNA polymerase is a multi-subunit protein complex whose fundamental purpose is to catalyze the chemical reaction of transcription: synthesizing a complementary RNA strand from a DNA template.As a DNA-dependent RNA polymerase, its enzymatic activity involves binding to promoter sequences on DNA, unwinding the DNA double helix, aligning ribonucleotides (ATP, UTP, GTP, CTP), catalyzing the formation of phosphodiester bonds to build the RNA chain, proofreading, and terminating at specific terminator sequences.A) To become a proteinRNA polymerase is a protein—it is an enzyme composed of polypeptide chains. Its purpose is not to "become" what it already is, but to perform a specific catalytic function. This option confuses the nature of the molecule with its function.B) To become a nucleotideNucleotides are the monomeric substrates that RNA polymerase uses to build an RNA chain. The enzyme catalyzes the bonding of nucleotides; it does not transform into a nucleotide itself.C) To function as an enzymeThis is the accurate description. Its raison d'être is its enzymatic activity, to transcribe DNA into RNA (mRNA, tRNA, rRNA), which is the first step in gene expression.D) To develop into a terminatorA terminator is a specific DNA sequence that signals RNA polymerase to stop transcription and release the RNA transcript. The terminator is a sequence the enzyme recognizes and responds to, not something the enzyme becomes. The enzyme's purpose is to synthesize RNA until it encounters this signal.Conclusion:RNA polymerase is a molecular machine whose core purpose is enzymatic catalysis. It does not transform into its substrates (nucleotides) or into a termination signal. It is already a protein. Its defined role in the cell is to function as the enzyme that carries out transcription.

What is the purpose of RNA polymerase?

A
To become a protein

B
To become a nucleotide

C
To function as an enzyme

D
To develop into a terminator

RNA polymerase is a multi-subunit protein complex whose fundamental purpose is to catalyze the chemical reaction of transcription: synthesizing a complementary RNA strand from a DNA template.

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What is the purpose of RNA polymerase?

A To become a protein B To become a nucleotide C To function as an enzyme D To develop into a terminator

RNA polymerase is a multi-subunit protein complex whose fundamental purpose is to catalyze the chemical reaction of transcription: synthesizing a complementary RNA strand from a DNA template.

Topic Flashcards

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Related Questions

A
To become a protein

B
To become a nucleotide

C
To function as an enzyme

D
To develop into a terminator