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DNA, or deoxyribonucleic acid, consists of two intertwined strands forming a double helix.Each strand is made up of repeating units called nucleotides. A nucleotide has three main components.First, a deoxyribose sugar, which forms the backbone of the DNA strand.Second, a phosphate group that links the sugars together.The third component is a nitrogenous base. There are four types of bases in DNA: Adenine, Thymine, Guanine, and Cytosine.These bases pair up specifically: Adenine pairs with Thymine using two hydrogen bonds.And Guanine pairs with Cytosine using three hydrogen bonds. This specific base pairing is crucial for DNA's function.These nucleotides are arranged in a specific sequence along the DNA molecule, forming the genetic code that carries our biological information.DNA replication begins with the separation of the two strands by helicase enzyme.As helicase moves along the DNA, it breaks the hydrogen bonds between base pairs, creating a replication fork.DNA polymerase then begins synthesizing new strands. On the leading strand, synthesis occurs continuously in the five prime to three prime direction.On the lagging strand, synthesis occurs discontinuously in short segments called Okazaki fragments.The leading strand is synthesized continuously in the five prime to three prime direction, while the lagging strand is made in short segments in the opposite direction.These Okazaki fragments will later be joined together by DNA ligase to form a continuous strand.