What is the role of the enzyme DNA ligase?
Answer and explanation
Correct answer: C. It seals gaps in the sugar–phosphate backbone
- Step 1: The lagging strand is made as Okazaki fragments.
- Step 2: DNA ligase joins the fragments to form a continuous strand.
Answer
It seals gaps in the sugar–phosphate backbone.
Why not the others: It unwinds the DNA helix: this is helicase. It adds nucleotides to the primer: this is DNA polymerase. It cuts DNA at specific base sequences: this is a restriction enzyme.
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