Student Question

NADH and FADH2 are classified as which of the following?


Expert Answers

An illustration of the letter 'A' in a speech bubbles

NADH and FADH2 are both examples of coenzymes.

Coenzymes are small, organic substances. Unlike enzymes, coenzymes are not proteins. Some coenzymes are vitamins. Although coenzymes are not catalytic by themselves, they can help enzymes increase the rate of reactions (“co” = together). When bound together, the coenzyme-enzyme complex forms an active enzyme called the holoenzyme. Although coenzymes bind with enzymes, coenzymes are not considered to be the substrate of the enzyme.

NADH and FADH2 are coenzymes that are both present during cellular respiration. NADH and FADH2 are both produced during the Krebs Cycle of cellular respiration. The electrons carried by NADH and FADH2 are then used during the electron transport chain of cellular respiration when ADP (adenosine diphosphate) is phosphorylated into ATP (adenosine triphosphate).

See eNotes Ad-Free

Start your 48-hour free trial to get access to more than 30,000 additional guides and more than 350,000 Homework Help questions answered by our experts.

Get 48 Hours Free Access
Approved by eNotes Editorial