Question

Which of the following molecules forms lengths of DNA with ‘sticky ends’?

Options

• DNA ligase

• DNA polymerase

• RNA polymerase

• Restriction enzyme

Answer 1

Restriction enzyme

Explanation:

Restriction enzymes cut DNA at specific recognition sequences, producing fragments with either ‘sticky ends’ or ‘blunt ends’. Sticky ends are single-stranded overhanging sequences at the DNA fragment ends generated by staggered cuts. These sticky ends can easily pair with complementary sequences from other DNA fragments, facilitating the formation of recombinant DNA. Restriction enzymes facilitate the formation of sticky ends, which are then joined by DNA ligase. This is crucial in genetic engineering for joining DNA fragments.