Essay on Replication Replication occurs during the S Phase of the cell cycle. Initiator proteins begin the process. The strands are separated by the enzyme helicase. DNA polymerase begins replicating the leading strand in the 5' to 3' direction since DNA is antiparallel. The other strand, or the lagging strand, uses primase to copy the strand in the 5' to 3' direction but it only does a few nucleotides at a time. These fragments are …showed first 75 words of 215 total…

…showed last 75 words of 215 total…begin the strand so RNA primase is used to do about the first ten nucleotides. This beginning is called a primer and is later replaced with DNA molecules. The single-strand-binding proteins also help keep the strands apart. Nuclease cuts out the bad nucleotides. Telomeres are the sequences at the end of the strands that do not particularly code for anything but the shorter they get the less likely it is that that cell will reproduce.