Overview Structure long chain of carbons with carboxyl group on one end can have a variable amount of double bonds double bonds make a fat unsaturated naturally in a cis configuration login to view 2 more bullets double bonds ↓ melting temperature login to view 2 more bullets nomenclature e.g. palmitic acid login to view 3 more bullets e.g. linoleic acid login to view 2 more bullets omega system login to view 5 more bullets Essential fatty acids (FA) cannot be synthesized examples linoleicacid login to view 3 more bullets linolenic acid login to view 4 more bullets Transport see Lipoprotein topic Synthesis FA synthesis pyruvate (carbohydrate) → acetyl-CoA activated by insulin functions to store excess carbs as fat occurs in the mitochondria via pyruvate dehydrogenase acetyl-CoA + oxaloacetate → citrate shuttled out of mitochondria into cytoplasm login to view 1 more bullet split back to acetyl-CoA and oxaloacetate acetyl-CoA + CO2→ malonyl-CoA catalyzed by acetyl-CoA carboxylase biotin required activated by insulin malonyl-CoA → CO2 + 2 carbons on fatty chain catalyzed by FA synthase requires NADPH humans make palmitic acid (16:0) as stored fat login to view 1 more bullet for 1 palmitic acid requires login to view 3 more bullets Catabolism Break down via β-oxidation occurs in hepatocytes, myocytes, adipocytes neurons cannot use fat as energy login to view 1 more bullet pathway location differs based on length of FAs short/medium (2-12 carbons) login to view 1 more bullet long (14-20 carbons) login to view 23 more bullets very long (>20 carbons) login to view 1 more bullet β-oxidation pathway occurs in the mitochondrial matrix reverses FA synthesis removing an acetyl-CoA and producing NADH and FADH2 login to view 5 more bullets creates most of the energy used by the liver login to view 3 more bullets clinical importance MCAD deficiency login to view 11 more bullets