In essence, every cell molecules that store the structure of life are deoxyribonucleic acid (DNA). DNA is composed of four types of molecules known as nucleic acids or nucleotides. The four DNA nucleic acids are: adenine (A), guanine (G), cytosine (C) and thymine (T). These molecules in turn are divided into two families. Adenine (A) and guanine (G) as purine and cytosine (C) and thymine (T) as a pyrimidine, unknown. While the synthesis of DNA nucleotidesconverted into nucleic acids, so they can be combined to form DNA strands. The DNA strand leads the assembled structure of a double helix.
The chemical structures of the four nucleotides are planar due to delocalized electrons in the 5:00 to 6:00 and membered rings, each with a thickness of 3.4 Angstrom. When the nucleotides of the double helix structure, AT and GC-shape are joined by a hydrogen bond, forming a base pair. The base pairs are then linked together with thesugar bonds to form the spiral. X-ray data shows that 10 base pairs per turn of helix.
The helix model of DNA nucleic acids, explains the theory of genetic replication. James Watson, once described him as " Pretty molecule, because the replication method is so evident in this structure. During replication, the breaking of hydrogen bonds between nucleotides and allow each individual strand of DNA serve as a replica of the other half for the model. The two identical copies of recent DNA nucleic acids are then distributed the new daughter cells. Like every replication cycle, half of that ancient DNA is obtained, DNA replication, is said to be semi-conservative.
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