<prompt> All of the following are Isoprene derivates Polyprenoids, except ?UbiquitinDolicholb-carotenea-tocopherol  <response>: Polyprenoids are a class of compounds synthesized from 5 carbon isoprene units. They include: Ubiquinone - electron carrier in respiratory chain Dolichol - long-chain alcohol involved in N-glycosylation Plant-derived Polyprenoids - rubber, camphor, the fat-soluble vitamins A, D, E, and K, and b-carotene provitamin A. Ubiquitin is not a pa of polyprenoids. It is a protein polypeptide. 