Fatty Acid Synthase (FAS) Differs from β-Oxidation in All of the Following

Question

Fatty acid synthase (FAS) differs from β-oxidation in all of the following ways EXCEPT:
A) occurs in cytosol.
B) uses NADPH for oxidoreductase reactions.
C) acyl carrier protein linked intermediates.
D) all of the enzymes are on one polypeptide.
E) all are true.

Accepted Answer

All of the statements are true, so the answer is "all are true." Fatty acid synthesis via FAS occurs in the cytosol and uses NADPH for reducing equivalents. Intermediates are linked to an acyl carrier protein during the synthesis, and all of the enzymes required for the synthesis of a fatty acid are on one polypeptide chain. The major difference between FAS and β-oxidation is the directionality of the process, with FAS building up fatty acids and β-oxidation breaking them down.