Question

unit exam - chemistry of life
within nucleic acids, which of these plays an important role in replacing damaged nucleotides?
mucus
enzymes
lipids

Explanation:

Enzymes, such as DNA polymerase in the given diagrams (DNA Polymerase III and DNA Polymerase I are shown in proof - reading and mismatch repair processes), are biological catalysts that facilitate chemical reactions. In nucleic acid metabolism, they play crucial roles in processes like DNA replication, repair (including replacing damaged nucleotides as depicted in mismatch repair and nucleotide excision repair). Mucus is a protective secretion (e.g., in the respiratory or digestive tracts) and has no role in nucleic acid nucleotide replacement. Lipids are a class of biomolecules (e.g., fats, phospholipids) involved in energy storage, membrane formation etc., not in nucleotide replacement within nucleic acids.

Answer:

enzymes