DNA replication
DNA replication is the biological mechanism that generates two identical copies of DNA from a single original DNA molecule.
The steps involved in the process of DNA replication are as follows:
1. Helicase initiates DNA replication by unzipping the double helix, breaking hydrogen bonds between complementary bases.
2. This separation forms a replication fork, where the two strands act as templates for new DNA synthesis.
3. The leading strand, oriented 3′ to 5′, has a primer attached by primase, initiating continuous DNA polymerase action.
4. The lagging strand, oriented 5′ to 3′, experiences discontinuous replication with the formation of Okazaki fragments.
5. Exonuclease removes primers, and DNA ligase connects Okazaki fragments, ensuring a continuous double-stranded DNA.
6. DNA replication, a semi-conservative process, results in two molecules, each with one old and one new chain, forming a double helix. Failure to follow cell division post-replication leads to polyploidy due to accumulated DNA.