Difference in between Nucleotides and Nucleosides

Nucleotides and Nucleosides

Nucleotides are said to be the building blocks of nucleic acids. What are Nucleosides then? Are the two components same? Or is there some difference between them? Yes, they are different. The main difference lies in their molecular composition. Nucleosides contain only pentose sugar and a base whereas Nucleotides contain pentose sugar, base and a phosphate group as well. Let us clear this concept with the help of the given illustration and then practicing the given question.