All living cells contain both DNA and RNA, and their DNA and RNA use the same purines (Adenine and Guanine) and pyrimidines (Cytosine, Thymine (DNA), and Uracil (RNA)).
All living cells contain the 3 main types of RNA (mRNA, tRNA, and rRNA), and they all perform the same functions in all cells.
All living cells contain proteins, made of the "universal" core set of 20 amino acids.
All living cells carry out transcription (DNA used as template to make RNA) and translation (RNA used to synthesize polypeptides).
And in all living cells, translation occurs on ribosomes, which always consist of 2 subunits (LSU and SSU), and the ribosomes are made of both rRNA and proteins. As a rule (with a very few, small exceptions), the same "universal" genetic code (mapping of mRNA codons to amino acids) is used. The same amino acid is used for initiation: Methionine (or a modified form), and there are two different tRNAs for methionine: one for initiation and one for elongation. In translation, all cells use GTP (not ATP) for binding of aminoacyl-tRNA to A site on ribosome, and also for translocation of ribosome along mRNA. Elongation factors are used in all living cells.
