1. A phosphate group: This is a molecule containing phosphorus and oxygen. It provides the negative charge to DNA and helps link nucleotides together.

2. A deoxyribose sugar: This is a five-carbon sugar, specifically deoxyribose, which gives DNA its name. It acts as the backbone of the nucleotide.

3. A nitrogenous base: This is a molecule with nitrogen atoms that can be either adenine (A), guanine (G), cytosine (C), or thymine (T). These bases are responsible for storing genetic information.

These three components are joined together in a specific way: the phosphate group is attached to the 5' carbon of the deoxyribose sugar, and the nitrogenous base is attached to the 1' carbon of the deoxyribose sugar.

The sequence of nitrogenous bases along a strand of DNA is what determines the genetic information encoded.