Final answer:
DNA glycosylases are the enzymes that remove chemically modified nucleotides from DNA during nucleotide base excision repair.
Step-by-step explanation:
The enzymes that remove chemically modified nucleotides from DNA during nucleotide base excision repair are called DNA glycosylases. DNA glycosylases recognize and catalyze the removal of damaged or modified bases from the DNA molecule.
For example, in nucleotide excision repair, specific DNA glycosylases recognize and remove thymine dimers or other damaged bases caused by UV exposure. Once the damaged base is removed, the gap is filled with the correctly paired nucleotides by the action of DNA polymerase and the remaining gap is sealed by DNA ligase.