Krebs cycle (TCA)
MCAT glossary · MCAT
Definition
The mitochondrial-matrix cycle that fully oxidizes acetyl-CoA, yielding per turn 3 NADH, 1 FADH_2, 1 GTP, and 2 CO_2.
Krebs cycle (TCA) in plain English
The Krebs cycle is one stage in how your cells extract energy from food, running inside the mitochondria (the cell's tiny power plants). It takes a small carbon molecule called acetyl-CoA (made from the sugar and fat you eat) and completely "burns" it, spinning like a wheel that returns to its start each turn. Each turn it releases 2 molecules of CO_2 (the carbon you breathe out) and, more importantly, loads up energy-carrier molecules (3 NADH, 1 FADH_2) plus 1 GTP. Those carriers then hand their energy to the next stage, which makes most of the cell's usable fuel.
Also called: TCA
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