Krebs cycle (or tri-carboxylic acid, TCA, cycle)

Named after its discoverer, the biochemist Hans A. Krebs (1900-81), it is a series of biochemical reactions  essential to the metabolism of aerobic organisms. The enzymes of the cycle are located in the mitochondria and work in close association with the various components of the electron transport chain.  It involves interconversions of various acids, with decarboxylations and oxidations, and results in the reduction of NAD (nicotine adenine dinucleotide, a co-enzyme derived from vitamin B) and FAD (flavin sideline dinucleotide, a co-enzyme consisting of the phosphroylated vitamin Bs linked to the nucleotide adenine monophosphate) in producing acids that act as intermediaries in other syntheses. 

See Aerobic respiration, Biochemistry, Electron transport chain (or respiratory chain), Enzyme, Maximal aerobic power, Mitochondria, Phosphorylation