Which of the following statements about restriction enzymes is incorrect?

They are used to glue together short segments of DNA.

The correct answer is Option (3) -They are used to glue together short segments of DNA.

Restriction enzymes belong to a larger class of enzymes called nucleases. These are of two kinds; exonucleases and endonucleases .These are known as molecular scissors . Restriction enzymes, also known as restriction endonucleases, are enzymes that cut DNA at specific recognition sequences. They are not used to glue together DNA segments; instead, they cleave DNA molecules at precise nucleotide sequences. These enzymes are integral tools in molecular biology for DNA manipulation, allowing the precise cutting of DNA strands at specific locations. However, their primary function is to cut DNA, not to join or glue DNA segments together. DNA ligase is the enzyme responsible for joining DNA segments.

Therefore, the statement that restriction enzymes are used to glue together short segments of DNA is incorrect.