Final answer:
Beta-oxidation primarily occurs in the mitochondria, where fatty acids are broken down to produce acetyl CoA, which is then used in the Krebs cycle to generate ATP.
Step-by-step explanation:
Fatty acid oxidation, also known as beta-oxidation, primarily occurs in the mitochondria of the cell. The process begins in the cytoplasm where fatty acids are converted into fatty acyl CoA molecules. These molecules then combine with carnitine to create a fatty acyl carnitine molecule, which transports the fatty acid across the mitochondrial membrane. Inside the mitochondria, the fatty acyl carnitine is converted back into fatty acyl CoA and eventually into acetyl CoA. This acetyl CoA enters the Krebs cycle to produce ATP. While some fatty acid elongation takes place in the endoplasmic reticulum and peroxisomes are involved in oxidation of very long-chain fatty acids, the primary site for beta-oxidation is the mitochondrial matrix.