Yes, both DNA and RNA have nitrogenous bases. These bases are one of the key components of their structures, along with a sugar molecule and a phosphate group.

Here's a breakdown:

* DNA: Deoxyribonucleic acid has four nitrogenous bases: Adenine (A), Guanine (G), Cytosine (C), and Thymine (T).

* RNA: Ribonucleic acid also has four nitrogenous bases, but instead of thymine, it has Uracil (U). So, RNA's bases are: Adenine (A), Guanine (G), Cytosine (C), and Uracil (U).

These nitrogenous bases form the "rungs" of the DNA ladder or the "backbone" of RNA, and they are responsible for carrying and transmitting genetic information.