The process of DNA replication has been studied extensively as the pathway to understanding the processes of inheritance and the possible platform for addressing a range of health issues occurring as a result of DNA mutations.
However, the subject matter is still plagued by grey areas that require further analysis, the very properties of the process being one of the core issues of debating. Specifically, whether DNA replication can be deemed as semiconservative remains largely an unanswered question (Georgia Highlands College, n.d.). I believe that, despite the lack of certainty regarding the problem under analysis, it would be reasonable to believe that DNA replication is semiconservative since it is consistent with the fact that, during the reproduction process, DNS is separated into two bands.
The statement concerning DNA replication being a semiconservative process that leads to the development of two separate strands of DNA material has been supported by a vast range of evidence. Recent experiments point to the correctness of the semiconservative framework as the most legitimate theory that allows describing the process of DNA replication in the greatest detail possible (Georgia Highlands College, n.d.). In order to concede that the process of DNA replication is semiconservative, one should take a closer look at the outcomes of the experiment performed.
Since the test performed by Meselson and Stahl showed that the amount of the DNA material was equal in two daughter cells, yet the density thereof was different, the presence of semiconservative properties in DNA replication can be regarded as proven. By asserting that the observed tendency could be found in not only the strands of E.coli but also in other species, Meselson and Stahl made it evident that the DNA replication did, in fact, show semiconservative properties (Georgia Highlands College, n.d.). Thus, I insist that the existing evidence points to the DNA replication process being semiconservative.
The described outcomes of the experiment also lead to a vast range of conclusions concerning the nature and outcomes of DNA replications in different species. By defining DNA replication as semiconservative, the researchers made it evident that every double helix axis in the DNA structure built with the help of DNA polymerases leads to the creation of an entirely new strand that acts as complementary (Georgia Highlands College, n.d.).
It should also be borne in mind that the specified characteristic of the DNA structure makes it possible for the new strand, which is also known as the leading one, to emerge as a continuous piece, whereas the complementary one, or the lagging strand, occurs as a combination of smaller pieces (Georgia Highlands College, n.d.). By applying the notion of the DNA replication process being semiconservative, one can explain the observed changes within the DNA framework and provide the foundation for the further analysis of the subject matter.
Indeed, the results of the experiment described above cannot be deemed as consistent with the theory of dispersive replication, which has been offered as the alternative to the semiconservative framework. Using isotopes of nitrogen as the tools for labeling the DNA of the studied bacteria, Meselson and Stahl staged an experiment in the course of which the nature of the DNA replication process and the basis for its implementation were studied (Georgia Highlands College, n.d.). The semiconservative assumption made by the scientists implied that, in the process of replication, entirely new strands of DNA were produced with the help of the ones that were already present in the cells of the bacteria under analysis.
During the experiment, it was discovered that each of the nitrogenous bases presented in the DNA structure is only capable of connecting to its corresponding complementary partner. For adenine, the process of pairing occurs with thymine, whereas cytosine is connected to guanine in the process (Georgia Highlands College, n.d.). The resulting replication process, thus, takes place due to the combination of the helicase and DNA polymerase procedures (Georgia Highlands College, n.d.). Therefore, I strongly believe that the principle of DNA replication as the notion based on the semiconservative framework seems to be quite valid, given the vast amount of supportive evidence that has been collected.
Based on the outcomes of the Meselson–Stahl experiment, during which the DNA showed a strong propensity toward splitting into two distinct brands, the assumption that the DNA process is semiconservative can be regarded as confirmed. Even though it could be alleged that the current research has been erroneous and that the process of DNA replication may involve different processes and be based on an entirely different principle, the veracity of the identified statement is quite feeble. Thus, the stages of DNA replication can be seen as the semiconservative process. The presence of a synthesized strand along with the preexisting template one has proven to be the most sensible way of looking at the DNA replication stage.
Reference
Georgia Highlands College. (n.d.). Chapter 14 – DNA structure and function. Web.