Which two enzymes are primarily responsible for decomposing nucleotides into phosphate ions, pentose sugars, and nitrogenous bases?

• A. Polymerase and helicase
• B. Nuclease and phosphatase
• C. Ligase and isomerase
• D. Kinase and dehydrogenase

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the decomposition of nucleotides. Nucleotides consist of three main components: phosphate groups, pentose sugars, and nitrogenous bases. To break these down, specific enzymes are required to target each component.
2. Step 2: Identify the role of nucleases. Nucleases are enzymes that hydrolyze the phosphodiester bonds in nucleic acids, releasing individual nucleotides or nucleotide fragments. This is the first step in breaking down nucleotides.
3. Step 3: Recognize the role of phosphatases. Phosphatases are enzymes that remove phosphate groups from molecules, including nucleotides. This step releases free phosphate ions from the nucleotide structure.
4. Step 4: Understand why polymerase and helicase are incorrect. Polymerase synthesizes nucleic acids, while helicase unwinds DNA strands during replication. Neither enzyme is involved in nucleotide decomposition.
5. Step 5: Confirm that ligase, isomerase, kinase, and dehydrogenase are also incorrect. Ligase joins DNA fragments, isomerase rearranges molecular structures, kinase adds phosphate groups, and dehydrogenase is involved in oxidation-reduction reactions. None of these enzymes decompose nucleotides.