Correct Order Answer: In the presence of oxygen, glucose, fatty acids, and amino acids can be metabolized to produce a two-carbon molecule, acetyl-CoA. Correct Order Answer: Each acetyl-CoA molecules enters a circular pathway called the citric acid cycle, that produces two molecules of CO2. Correct Order Answer: Most of the energy released from glucose, fatty acid, or amino acid molecules is used to produce ATP, and oxygen combines with hydrogen to form water.