Identify the lagging strand during duplication of DNA starting from a double helix in the accompanying figure.
A) a
B) b
C) c
D) d

Question

Identify the lagging strand during duplication of DNA starting from a double helix in the accompanying figure.
A) a 
B) b 
C) c 
D) d

Quizplus · Accepted Answer

The lagging strand is the template strand that is replicated in the opposite direction of the replication fork movement. In the figure, the fork movement is from right to left, and the template strand on the right is replicated in the 5' to 3' direction continuously as the leading strand. The template strand on the left, however, is replicated in the opposite direction, so the new strand synthesis is in the opposite direction of the replication fork movement, resulting in Okazaki fragments. Therefore, the template strand on the left is the lagging strand, and the correct choice is C.

Identify the Lagging Strand During Duplication of DNA Starting from a Double