Inside a nucleotide
Every nucleotide is built from three kinds of component.
1. A nitrogenous base
A ring containing nitrogen. This is the part that carries the information — the order of the bases is itself the genetic code.
2. A pentose sugar group
A sugar with five carbon atoms. That makes it a carbohydrate — what you learned in section 1.1 turns up again here.
3. A phosphate group
The part that brings the phosphorus. It is also the part that links one nucleotide to the next.
How they join
The sugar sits in the middle. The base attaches to one side and the phosphate group to the other. The phosphate of one nucleotide bonds to the sugar of the next, and a long chain forms.
Extra knowledge — where the name comes from
"Nucleic" comes from nucleus — these acids were first found inside the cell nucleus.