Here's why:

* RNA is made of nucleotides: RNA, like DNA, is a nucleic acid. It is built from chains of nucleotides. Each nucleotide consists of a sugar (ribose), a phosphate group, and one of four nitrogenous bases (adenine, guanine, cytosine, and uracil).

* Amino acids are the building blocks of proteins: Proteins are different from nucleic acids. They are made from chains of amino acids linked together by peptide bonds.

* RNA and proteins work together: RNA plays a crucial role in protein synthesis. Messenger RNA (mRNA) carries the genetic code from DNA to ribosomes, where proteins are assembled. Transfer RNA (tRNA) carries specific amino acids to the ribosomes.

In summary, amino acids and RNA are different molecules with distinct roles in the cell. While they work together in protein synthesis, amino acids are not a part of the structure of RNA.