DNA Replication
DNA replication is the process of making two exact copies of the genetic information on a double-stranded DNA, so that one copy can be given to each of the two daughter cells produced when a cell divides. 16 This process begins when the double helix is opened up and copied into two single-stranded DNA molecules called daughter strands. The double-stranded DNA is unzipped by the enzyme helicase at an incredible speed, 1,000 nucleotides every second. 17 Spinning the DNA as fast as a jet engine to open the two strands. 18 Then, the two open strands offer templates for each of the new double-stranded DNA strand to be built. DNA polymerase, an enzyme, functions as a catalyst to add the complimentary nucleotides onto the exposed single strand of DNA, which is now accessible on the strand. The polymerase needs a primer to begin this process. Primase sends a replication signals to the polymerase in the form of RNA primers, (RNA) primase, which initiates process. Polymerase synthesizes the new DNA by adding the complementary nucleotides to form the two new daughter strands, exact copies of the original double stranded DNA. When the helicase opens the double-stranded DNA into the two single strands of DNA, it looks like a fork. Consequently, the site where this process occurs is referred to as the replication fork. 19 20
Comments: