All form of living creatures has a so-called thing Deoxyribonucleic acid or simply know by many as DNA, even the smallest and simplest form of living things possessed it like the virus, bacteria, and cells which is very essential to every existing creature like us, interesting right? DNA is one of the important reasons of our existence or without it the world will be in complete silence. So, let me define it, DNA is a nucleic acid that is consist of two chains that are bind in circling staircase to form a double helix which is consist of genetic instructions that essentially needed for a creature’s growth and survival. Furthermore, there is a process wherein the DNA makes a replica of itself during a cell division, it is called DNA replication. How does it work? Let me explain.
First step of the DNA replication is the Replication Fork Formation, before the replication start to happen the DNA which is said earlier to be a double helix that is bind together separate into two single strands. Then DNA should be loosening up its base pairs that forms up the two strand is it possible through the enzyme called as DNA Helicase which will successfully loosen its base pairs in order turn it into a Y shape thing called the replication fork. Then it all starts the replication, DNA strands have its direction whenever it separates it is known as the 5’(phosphate group) and 3’(Hydroxyl group) end. Directionality is a must know thing as it will show which side of strand will be connected to DNA backbone. For the reason that a replication fork is bi-directional its strand will be oriented in the 3’ to 5’(leading strand) direction while the other strand and the 5’ to 3’(lagging strand) which makes the orientation of its process different.
Second and third step is just the start of the replication called Primer Binding and Elongation as it makes a new prototype of each strands by adding, error checking and repairing each, on leading strand, a primer starts the DNA synthesis, then the addition of new nucleotide bases and after newly strand will be continuous, meanwhile the lagging strand also have multiple primers added Okazaki fragments and the newly strand called as discontinuous. It was all accompanied by the enzyme DNA Primase.
Finally, the last step is called Termination, after forming of new prototype strands(the continuous and discontinuous strands). New and appropriate bases will be added and RNA primers will be removed by an enzyme called exonuclease from the original strands. Another exonuclease will exist in order to replace the errors, to check or either remove as a “proofread” to the newly DNA. DNA ligase, another enzyme which joins up the Okazaki fragments which unified a strand. The ends of the chromosomes will be capped in order to stop the other chromosomes from fusing it is called Telomeres. On the other hand, Telomerase, generates telomere in sequence in ends of DNA. The complete results will be two DNA molecules, one new strand and parent molecule.
In conclusion, DNA replication is everything in all forms of life without it we won’t exist anymore. Knowing how it works is a really complicated as it has a lot of processes as it goes further to creates duplicates of itself. The process are replication fork, primer binding, elongation and the termination. Hence, DNA replication is playing an important role in our life as it sustains our growth and development as the time goes by making duplications of DNA.
Bibliography:
Bailey, R. (2018, December 22). Steps of DNA Replication. Retrieved March 29, 2019, from https://www.thoughtco.com/dna-replication-3981005
Rettner, R. (2017, December 07). DNA: Definition, Structure & Discovery. Retrieved March 29, 2019, from https://www.livescience.com/37247-dna.html
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