The nucleic acid found in ribosomes is ribonucleic acid (RNA). Specifically, there are two types of RNA found in ribosomes:

* Ribosomal RNA (rRNA): This is the major component of ribosomes, making up about 80% of the ribosome's mass. rRNA provides the structural framework for the ribosome and plays a crucial role in the translation process.

* Transfer RNA (tRNA): tRNA molecules bring amino acids to the ribosome, where they are incorporated into the growing polypeptide chain during protein synthesis.

While ribosomes are involved in protein synthesis, they themselves are not composed of DNA.