Why is DNA replication necessary?
DNA replication is an essential biological process common to all living organisms wherein the DNA chromosomes of a parent cell are exactly copied as it undergoes cell division for the continuation of cell development. It is critical in DNA replication that the new chromosomes duplicate in the same order as the old chromosome has or else mutation may occur.
DNA replication serves as the foundation of heredity or the passing of traits from parents to the offspring/s.
A simple way to describe how DNA replication works is through a zipper. The zipper itself represents a DNA chromosome. Although a zipper only have one type of tooth, the DNA chromosome has four teeth or nucleotides that includes A, T, C, and G. And these nucleotides follow a simple rule in pairing, A (longer) goes together with T (smaller) that is on the other side of the strand, while C (smaller) goes together with G (longer).
When it is time for the DNA chromosome to duplicate itself, pair of nucleotides is unzipped with each other and the floating free nucleotides will then match up with the old nucleotides on the strand creating a new pair: A and T, C and G. Bit by bit, nucleotides are being unzipped and then replicated until the old DNA chromosome has been totally changed into two new equal DNA strands.
The pairing of the nucleotides is automatic through a non-covalent bond. This type of bond helps keep the nucleotides in its place until it is time for another replication wherein the pairs are again unzipped apart.
DNA replication can also be done outside the cell which is called in vitro using polymerase chain reaction (PCR). This scientific approach is used to copy a piece of DNA chromosome into hundreds, thousands, or millions of replicas for laboratory use. This technique can be used in determining evolutionary interconnection between organisms, forensic analysis, study of prehistoric DNA, and in diagnosis of various diseases.