DNA is an organic polymer made that carries information or genetic instructions for the manufacture of protein for the cell. The genetic code uses for nucleotide bases which are repeated in sequences for particular amino acids. Amino acids are the building blocks of protein.
THE DNA molecule consists of two long polymer strands that are wrapped around each other producing a double helix structure. The structure is similar to a long rope ladder that has been twisted into a continuous spiral shape.
The repeating monomer that makes up DNA is one of four nucleotides. Each nucleotide is composed of a nitrogenous base, a five carbon sugar, deoxyribose and a phosphate group.
The four nucleotide bases that are used to code the information are thymine (T), adenine (A), cytosine (C) and guanine (G).
The four nitrogenous bases from each polymer strand are joined together by hydrogen bonds (adenine(A) joins with thymine(T) and cytosine(C) joins with guanine(G)). These chemical bonds hold the two polymer strands together. Each pair of joining nucleotides (AT or GC) are like the rungs in a ladder which joins the two sides.