The process of DNA replication begins with one double-stranded molecule of DNA. The two strands of this molecule separate during replication, and DNA polymerases add complementary nucleotides to each strand. The end results of DNA replication are two identical DNA molecules
<span>In bacteria, DNA polymerase adds an incorrect base to a growing strand of DNA about once in every 100 000 bases added. The result is a mismatch such as the pairing of A with C.
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