Question

dna replication
learning objective 19.3: describe the function of major components of the replisome: helicase, topoisomerase, dna polymerase, dna ligase, and primase.
which enzymes are needed more frequently on the lagging strand compared to the leading strand? select all that apply.
☐ helicase
☐ ligase
☐ primase
☐ topoisomerase

Explanation:

1. Helicase: Unwinds DNA at the replication fork, used equally on leading and lagging strands.
2. Ligase: Joins Okazaki fragments on the lagging strand (many fragments → more ligase use).
3. Primase: Synthesizes RNA primers. Lagging strand has multiple Okazaki fragments, so more primers (more primase use).
4. Topoisomerase: Relieves supercoiling, used equally on both strands.

So ligase and primase are needed more on the lagging strand.

Answer:

B. ligase, C. primase