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DNA replication and Origin of Replication in Bacteria - Straightforward question

The textbook I'm reading from says:
"DNA replication begins at a single origin of replication, and the two replication forks assembled there proceed (at approximately 500-1000 nucleotides per second) in opposite directions until they meet up roughly halfway around the chromosome."

Does the replication stop halfway ? Why did they say "until they meet up roughly halfway around the chromosome."

Reply 1

Kallisto

Entertainment Forum Helper

Original post by Leah.J

The replication stops when the enzyme ligase connected the last nucleotide in the new and replicated strands, not sooner!

In DNA replication, there are two newly synthesized strands going in different directions, because these two strands have different positions of their primers where the replication starts. The one syntheized strand goes in direction of the replication fork (from 5' to 3'), the other against it (from 3' to 5'), so in opposite direction. That is to say these newly strands approach during replication process and meet up at a certain segment of the DNA, that is roughly halfway around the Chronosome. After that they disappear from each other.