A nucleotide is the basic building block of nucleic acids such as RNA and DNA. It is composed of three main parts:
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Sugar: The sugar component of the nucleotide is a five-carbon sugar. Deoxyribose or 2-deoxyribose is the five-carbon sugar that is found in DNA, whereas ribose is found in RNA. The primary difference between the two sugars is the replacement of hydroxyl group by hydrogen at the 2’ position in deoxyribose.
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Nitrogenous Base: Nitrogenous bases are nitrogen-containing basic compounds. There are a total of five bases found in the DNA and RNA world, namely – Adenine (A), Cytosine (C), Guanine (G), Thymine (T) and Uracil (U) . A, T, C, and G are found in DNA molecules, whereas the uracil base is found in RNA.
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Phosphate Group: The phosphate group is attached to the sugar molecule and a nitrogen-containing base. It is composed of one to three phosphates.
These three parts are joined together to form a nucleotide, which is also termed a "nucleoside monophosphate", "nucleoside diphosphate" or "nucleoside triphosphate", depending on how many phosphates make up the phosphate group.
