Question

The enzyme helpful in polymerizing RNA with defined sequences in a template-independent manner is:

• A. Mononucleotide phosphorylase
• B. Polynucleotide phosphorylase
• C. RNA polymerase - I
• D. DNA-dependent RNA polymerase

Answer 1

The Correct Option is B

The question asks for the enzyme that can polymerize RNA in a template-independent manner. Let's analyze the given options: 

• Mononucleotide phosphorylase: This enzyme does not play a role in RNA polymerization. It is involved in phosphorolysis of nucleotide monophosphates.
• Polynucleotide phosphorylase: It is capable of polymerizing ribonucleotides into RNA without a template. Thus, it can synthesize RNA with defined sequences in a template-independent manner.
• RNA polymerase - I: This enzyme is responsible for transcribing ribosomal RNA (rRNA) and requires a DNA template.
• DNA-dependent RNA polymerase: This enzyme catalyzes the synthesis of RNA using a DNA template and is template-dependent.

Thus, the correct enzyme that polymerizes RNA in a template-independent manner is Polynucleotide phosphorylase.

Answer 2

The enzyme that is helpful in polymerizing RNA with defined sequences in a template-independent manner is Polynucleotide phosphorylase.

(1) Mononucleotide phosphorylase: This enzyme catalyzes the formation of nucleotides from their corresponding mononucleotides, but it does not polymerize RNA.

(2) Polynucleotide phosphorylase: This enzyme is involved in the template-independent polymerization of RNA. It can add nucleotides in a sequence without a DNA or RNA template, making it essential for polymerizing RNA with defined sequences.

(3) RNA polymerase - I: This enzyme is responsible for synthesizing RNA from a DNA template, but it is not template-independent.

(4) DNA-dependent RNA polymerase: This enzyme synthesizes RNA based on a DNA template, and is not template-independent.

Thus, the correct answer is (2) Polynucleotide phosphorylase.