Nucleotides are the molecules (monomers) from which DNA and RNA are formed
Each nucleotide is formed from pentose, a nitrogen containing organic base and a phosphate group
The components of a DNA nucleotide are deoxyribose, the phosphate group and one of the organic bases:
Adenine (A)
Cytosine (C)
Guanine (G)
Thymine (T)
The components of a RNA nucleotide are ribose, the phosphate group and one of the organic bases:
Adenine (A)
Cytosine (C)
Guanine (G)
Uracil (U)
A condensation reaction between two nucleotides forms a phosphodiester bond.
Each nucleotide in DNA/RNA is joined together by these phosphodiester bonds between the pentose sugars; this is often described as a sugar-phosphatebackbone.