<unk>  <unk>  or<unk> ol) is an enzyme that makes an<unk>  copy of a DNA or<unk>  template. In cells,<unk>  is needed for constructing<unk>  chains from DNA genes, a process called transcription.<unk>  enzymes are essential to life and are found in all organisms and many viruses. In chemical terms,<unk>  is a nucleotidyl transferase that<unk> ymerizes ribonucleotides at the 3' end of an<unk>  transcript.
RNA polymerase
DNA polymerase
Ribozyme
Enzyme
Ligase
Caspase
Restriction enzyme
Deoxyribonuclease