The process of copying and duplicating a DNA molecule in a semiconservative way, i.e. the copy contains one of the original strands paired with a newly synthesized strand that is complementary in terms of AT and GC base pairing
DNA replication is a wondrous complex process whereby the original (parent) strands of DNA in the double helix are separated and each one is copied to produce a new (daughter) strand. This process is said to be semi-conservative since one of each parent strand is conserved and remains intact after replication has taken place. Several enzymes, e.g. DNA polymerases, are involved in DNA replication. After replication, copies of DNA molecule are checked by proofreading mechanisms.
DNA carries the genetic information that codes for a particular protein. One of the parental strands of the DNA molecule is replicated by base pairing so that the newly synthesized strand would be complementary to the original or parent strand. That is the purine nucleobase (i.e. adenine and guanine) is paired with the pyrimidine nucleobase (i.e. cytosine and thymine). In particular, the adenine will be paired with thymine while guanine with cytosine.
DNA replication is necessary in cell division. In the early stages of mitosis (prophase) and meiosis (prophase I), DNA is replicated in preparation for the late stages where the cell divides to give rise to two cells containing identical copies of DNA. DNA replication can be carried out artificially through a laboratory technique called polymerase chain reaction that can amplify the target DNA fragment from the genome.