Eat Right Practice Exam

The breakdown of fatty acids to yield acetyl-CoA is known as:

1. Glycolysis

2. Lipolysis

3. Ketogenesis

4. Beta-oxidation

The correct answer is: Beta-oxidation

The breakdown of fatty acids to yield acetyl-CoA is known as beta-oxidation. This metabolic process occurs primarily in the mitochondria of cells, where fatty acids are sequentially cleaved into two-carbon units, which are acetyl-CoA molecules. Each cycle of beta-oxidation involves the removal of two carbon atoms from the fatty acid chain, producing one acetyl-CoA each time, along with reducing equivalents in the form of NADH and FADH2, which are vital for ATP production in the electron transport chain. Beta-oxidation is a crucial step in lipid metabolism, allowing the organism to convert stored fat into usable energy, especially during periods of fasting or intense exercise when glucose may not be readily available. It is important to recognize that while lipolysis refers to the breakdown of triglycerides into glycerol and free fatty acids, it does not directly produce acetyl-CoA. Therefore, beta-oxidation is specifically the correct term that describes the conversion of fatty acids into acetyl-CoA, serving as a key pathway for energy metabolism.