Final answer:
Most electron carriers are coenzymes, such as NAD and FAD, which work with enzymes to facilitate biochemical reactions.
Step-by-step explanation:
Most electron carriers are coenzymes. Coenzymes are organic molecules that work with enzymes to facilitate biochemical reactions. They accept and donate electrons, acting as carriers in electron transport chains. Examples of coenzymes include NAD (nicotinamide adenine dinucleotide) and FAD (flavin adenine dinucleotide).