Final answer:
DNA replication is a process where DNA unwinds and nucleotides are added to form two complementary strands. DNA polymerase III plays a critical role by synthesizing new DNA in the 5' to 3' direction, and the method is semiconservative as it conserves half of the parent DNA in each daughter molecule.
Step-by-step explanation:
DNA Replication Process
The process of DNA replication begins when DNA unwinds at the origin of replication. Helicase then opens up the DNA to form replication forks, which extend in both directions. During this process, single-strand binding proteins stabilize the unwound DNA, and topoisomerase prevents supercoiling ahead of the fork. DNA polymerase III is crucial in this process, as it can add nucleotides only in the 5' to 3' direction. Thus, the leading strand is synthesized continuously, while the lagging strand is synthesized in Okazaki fragments. The RNA primers are eventually removed by exonuclease activity, gaps filled by DNA pol I, and finally, DNA ligase seals the strands, preserving the double helix's integrity.
In terms of DNA polymerase's function, it is the enzyme that adds nucleotides to the growing DNA strand during replication, ensuring the new strands are complementary to the original. It requires a primer to begin synthesis and operates in the direction from the 5' end to the 3' end of the new DNA strand. The process of DNA replication is termed semiconservative, because each new DNA molecule consists of one original and one new strand, conserving half of the parent molecule in each daughter molecule.