<unk> <unk> s are an important source of energy for many organisms. Excess glucose can be stored efficiently as fat. Triglycerides yield more than twice as much energy for the same mass as do carbohydrates or proteins. All cell membranes are built up of phospholipids, each of which contains two<unk> <unk> s.<unk> <unk> s are also used for protein modification.  The<unk>  of<unk> <unk> s, therefore, consists of catabolic processes which generate energy and primary metabolites from<unk> <unk> s, and anabolic processes which create biologically important molecules from<unk> <unk> s and other dietary carbon sources.
Lipolysis is carried out by lipases.
Once freed from glycerol, free<unk> <unk> s can enter blood and muscle fiber by diffusion.
Beta oxidation splits long carbon chains of the<unk> <unk>  into acetyl CoA, which can eventually enter the TCA cycle.
Briefly, β-oxidation or lipolysis of free<unk> <unk> s is as follows:
This cycle repeats until the FFA has been completely reduced to acetyl-CoA or, in the case of<unk> <unk> s with odd numbers of carbon atoms, acetyl-CoA and 1 mol of propionyl-CoA per mol of<unk> <unk> .
Fatty acid metabolism
Carbohydrate metabolism
Cellular respiration
Drug metabolism
Lipogenesis
Chiral pool synthesis
Arndt-Eistert synthesis
Cell signaling