AP BIOLOGY

Detailed explanation-1: -When replication begins, the two parent DNA strands are separated. One of these is called the leading strand, and it runs in the 3’ to 5’ direction and is replicated continuously because DNA polymerase works antiparallel, building in the 5’ to 3’ direction.

Detailed explanation-2: -Leading and lagging strands One new strand, the leading strand, runs 5’ to 3’ towards the fork and is made continuously. The other, the lagging strand, runs 5’ to 3’ away from the fork and is made in small pieces called Okazaki fragments.

Detailed explanation-3: -DNA is always synthesized in the 5’-to-3’ direction, meaning that nucleotides are added only to the 3’ end of the growing strand.

Detailed explanation-4: -DNA polymerase proceeds in the 5’ to 3’ direction down DNA. This means the leading strand will be synthesized continuously, as the replication fork opens at the 3’ end. The lagging strand, however, will be synthesized in discontinuous fragments called Okazaki fragments.