Continous and discontinuous Dna replication
Answers
Answer:
Continuous DNA Replication
When the parent DNA strands split at the start of replication, the double helix separates beginning at an internal point (the replication origin). One parent strand is oriented in a 5'-to-3' direction, and the other strand oriented in a mirror configuration, from the 3'-to-5' direction. DNA polymerase, the enzyme responsible for facilitating replication, only works in the 5'-to-3' direction. This means that the daughter strands must replicate in two different ways. For the ideally oriented strand, replication can occur continuously, progressing in the same direction as the replication fork, with nucleotides being added one by one. The daughter strand which replicates in this manner is referred to as the leading strand.
Discontinuous DNA Replication
The remaining daughter strand is aligned in the 3'-to-5' antiparallel direction. As polymerase molecule only works in the parallel direction, DNA replication on this strand can only occur in segments, away from the replication fork. Chunks of the antiparallel lagging strand, called Okazaki fragments, are replicated in the 5'-to-3' prime direction, moving back toward the replication fork. Eventually, these fragments are rejoined together by the enzyme DNA ligase, creating a continuous strand.