Process Of Dna Replication example essay topic

315 words
To understand the process of DNA replication, you much first be familiar with the structure of DNA. Resembling a twisted ladder, DNA is a double helix formed with nucleotides, a phosphate and sugar backbone, and nitrogenous bases. There are four bases, and each one will only bond with it's complement. Adenine will only bond with Thymine, and Cytosine with only Guanine.

The double helix is antiparallel, meaning each strand runs in a different direction. The first step to DNA replication is the unwinding of the double helix with the help of an enzyme called helicase. Once unwound, the DNA unzips and the bonded nucleotides are separated. In the next stage, an enzyme called DNA polymerase is important. The DNA polymerase attaches to each strand at the replication origins, reading the nucleotides and finding the complement base. Because the leading strand runs in the same direction that it was unzipped, the DNA polymerase moves with ease down the length of the strand.

The lagging strand, however, runs in the opposite direction that it was unzipped, making it harder for the DNA polymerase to down the strand, so it keeps returning to the strand until the job is done. Proof reader enzymes then run down the strand detecting and fixing errors. To complete the replication, the new strands are paired with their corresponding original strands. This is called semi-conservative because there is one new and one old strand combined. The strands are rewound into a double helix with the help of enzymes. The cell then prepare for mitosis where a copy of the DNA will be sent to each nucleus, then cells will go through cytokinesis, where a nucleus will be distributed to each cell.

This process has provided the daughter cell with an exact copy of DNA from it's parent.