What is used to break DNA into smaller pieces

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restriction enzymes (or restriction endonucleases) are used to cut DNA into smaller fragments.

Explanation:

The cuts are always made at specific nucleotide sequences. Different restriction enzymes recognise and cut different DNA sequences.

In the laboratory, restriction enzymes (or restriction endonucleases) are used to cut DNA into smaller fragments. The cuts are always made at specific nucleotide sequences. Different restriction enzymes recognise and cut different DNA sequences.