Here's the breakdown:

* DNA is a double helix - Imagine a twisted ladder.

* The sides of the ladder are made of sugar (deoxyribose) and phosphate groups, alternating in a chain.

* The rungs of the ladder are made of the four nitrogenous bases:

* Adenine (A)

* Thymine (T)

* Guanine (G)

* Cytosine (C)

Adenine always pairs with thymine (A-T) and guanine always pairs with cytosine (G-C). These base pairs are held together by hydrogen bonds.

The sequence of these base pairs along the DNA molecule carries the genetic information that makes you unique!