Notes

Dna replication is the process by which DNA makes a copy of itself. In eukaryotic organisms, this DNA replication occurs in the S phase of the cell cycle. Replication occurs at different sites until the replication forks come together to form two different strands. In prokaryotic organisms like bacteria, the DNA is replicated before the completion of binary fission. Replication begins at one end and replicates all around the DNA ring until a new strand is formed. Three postulated theories came about to predict the process of of DNA replication: The Semi-conservative Theory, The Conservative Theory, and the Dispersive Theory. The Semi-conservative theory suggests that the DNA would split in half and then the new copies will form on either side. The Conservative theory suggests that the first DNA remains intact and creates a photocopy of itself. The Dispersive theory is a combination of both the Semi-conservative and Conservative theories, suggesting that the DNA molecules get replicates in small bits and fragments. The Meselson-Stahl experiment was undergone with two different types of nitrogen (N15 and N14) to figure out that the Semi-conservative theory was factual. In other words, you begin with one strand and result in two identical strands with half of the original DNA. DNA consists of three parts: a sugar (deoxyribose), a phosphate group, and a nitrogenous base. DNA runs next to each other almost parallel like, but is anti-parallel in