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• beta-oxidation • Calvin cycle • choline-folate-methionine • glycolysis • HMG-CoA-reductase pathway • Krebs cycle • nitrogen assimilation • oxidative phosporylation • pentose-phosphate pathway • photorespiration • sulfur metabolism • urea cycle • chloroplast • ghrelin, leptin, melanocortin, obestatin

http://krebbing.blogspot.com/2006/12/sulfur-metabolism.html