The Transfer RNA's are responsible for attaching to a specific amino acid by base pairing. The transfer RNA molecules then proceed to the ribosomes where the messenger RNA is attached to a ribosome. The Two Hydrogen atoms came from the oxidation of another organic Biochemical species that was involved in an oxidative process. In Biochemical terms oxidation is thought to occur with the loss of Hydrogen atoms from a molecular system. Reduction would be the adding of hydrogen atoms to a molecular system.
Reverse reaction predominates during the reduction of another molecule.
Both of these function as co-enzymes in complex B vitamins are are referred to as dehydrogenases since they cause other molecules to lose Hydrogen atoms and become oxidized. It is called a dehydrogenase. Menu R. H. Logan, Instructor of Chemistry, Dallas County Community College District, North Lake College.