14. DNA Synthesis

Which is involved in replicating the lagging strand of DNA, but is not involved in leading strand replication?

Which of the following statements correctly describes the difference between the leading and the lagging strands of DNA during DNA replication?

The mechanisms of DNA synthesis differs between the two new daughter strands during replication. This is due to the fact that:

Below is a close-up of the portion of a DNA replication bubble.

Helicase is shown as a yellow triangle currently moving from left to right. Based on what you know about the creation of new DNA during replication, which is the lagging strand and why?

What is the basis for the difference in how the leading and lagging strands of DNA molecules are synthesized?

a. The origins of replication occur only at the 5′ end.

b. Helicases and single-strand binding proteins work at the 5′ end.

c. DNA polymerase can join new nucleotides only to the 3′ end of a pre-existing strand, and the strands are antiparallel.

d. DNA ligase works only in the 3′→5′ direction.

How are Okazaki fragments synthesized?

a. By using the leading-strand template, and synthesizing 5'→3'

b. By using the leading-strand template, and synthesizing 3'→5'

c. By using the lagging-strand template, and synthesizing 5'→3'

d. By using the lagging-strand template, and synthesizing 3'→5'.

The elongation of the leading strand during DNA synthesis

a. Progresses away from the replication fork

b. Occurs in the 3′→5′ direction

c. Produces Okazaki fragments

d. Depends on the action of DNA polymerase