<prompt> Ubiquitin is called so as:Present in all eukaryotic cellsTakes pa in impoant reactionsIs highly conservedNone of the above  <response>: Ubiquitin, so named because it is present in all eukaryotic cells, is a small 8.5 kDa, 76 residues polypeptide that targets many intracellular proteins for degradation. The primary structure of ubiquitin is highly conserved. Ref: Harper 28th edition, chapter 28. 