What is the primary role of nucleases in biological systems?

• A. Enzymes that digest nucleotides
• B. Enzymes that digest carbohydrates
• C. Enzymes that synthesize nucleic acids
• D. Enzymes that repair DNA

Answer: (A)

The primary role of nucleases in biological systems is to act as enzymes that digest nucleotides. Nucleases are specific enzymes that break down nucleic acids (DNA and RNA) into smaller components, such as nucleotides or oligonucleotides, by hydrolyzing the phosphodiester bonds between them. This process is critical in various biological functions, including DNA replication, repair, and degradation of RNA molecules, enabling cells to recycle nucleotides and manage genetic information.

While other enzyme functions like synthesizing nucleic acids (which is performed by polymerases) and repairing DNA (which is handled by repair enzymes) are essential in cellular functioning, they are not the primary role attributed to nucleases. Nucleases specifically target the breakdown of nucleotides, making option A the most accurate choice to identify the main function of these enzymes in biological systems.