Final answer:
The coenzyme form of riboflavin is flavin adenine dinucleotide (FAD), involved in the cellular energy production processes, cycling between its oxidized form FAD and reduced form FADH₂.
Step-by-step explanation:
The coenzyme form of riboflavin is flavin adenine dinucleotide (FAD). Riboflavin, also known as vitamin B2, is critical in the body's energy production processes. It has a role in the oxidation-reduction reactions within the cell by cycling between two forms: the oxidized form, FAD, and its reduced form, FADH₂. This cycling allows for the temporary storage and transfer of electrons, which is essential in cellular metabolism, particularly during energy extraction from sugars. Furthermore, NADP+ is a related coenzyme to NAD+, with the addition of an extra phosphate group, and this plays an important role in anabolic reactions and photosynthesis, especially in plants.