Final answer:
FAD can take part in either one or two electron oxidations, where the redox reactions occur at the flavin part of the molecule, not at the adenosine group.
Step-by-step explanation:
Flavin adenine dinucleotide (FAD) is a crucial coenzyme involved in oxidation-reduction reactions. The correct statement regarding the flavin nucleotides is that they can take part in either one or two electron oxidations. FAD is composed of an adenosine diphosphate (ADP) and a flavin mononucleotide, which is derived from riboflavin (vitamin B2). The redox reactions involving FAD occur at the flavin part, which contains nitrogen atoms that are capable of accepting and donating electrons. When FAD is reduced to FADH2 by reacting with two hydrogen atoms, two electrons are accepted (2 H+ + 2 e−). Unlike FAD, NAD+ (nicotinamide adenine dinucleotide) accepts a hydride ion (H−) during its reduction process, which is not the case for FAD.