Lipids

• Important respiratory substrates particularly in mammalian skeletal muscle, triglycerides are hydrolysed to form fatty acids and glycerol; converted to pyruvate and respired
• Fatty acids have long hydrocarbon chains, and therefore many hydrogen atoms which is a source of many protons for chemiosmosis, each combines with coenzyme-A (requires energy from hydrolysis of ATP to AMP + 2Pi)
• Fatty acid-CoA complex enters mitochondrial matrix where 2C acetate groups are successively removed from fatty acid, and combined with CoA; β-oxidation pathway of long chain fatty acid produces many reduced NAD and FAD