Final answer:
The metabolism of triglycerides and phospholipids results in glycerol, free fatty acids, and other components, which enter pathways like glycolysis, β-oxidation, and the citric acid cycle to produce energy in the form of ATP.
Step-by-step explanation:
The final products of the metabolism of triglycerides and phospholipids are glycerol, free fatty acids, and in the case of phospholipids, additional components such as the phosphorylated head groups. Glycerol can be further metabolized into glycerol-3-phosphate and then into glyceraldehyde-3-phosphate, which continues through the glycolysis pathway. Fatty acids undergo a process known as β-oxidation, which takes place in the mitochondria, breaking down the fatty acids into two-carbon acetyl groups. These acetyl groups are then picked up by coenzyme A (CoA) to form acetyl CoA, which enters the citric acid cycle (Krebs cycle). Here, they are eventually metabolized to carbon dioxide (CO2) while producing ATP, NADH, and FADH2. The NADH and FADH2 produced can be used in oxidative phosphorylation to create additional ATP, which supplies energy to the cell.