Krebs Cycle
Definition
The Krebs cycle (citric acid cycle or TCA cycle) is a series of chemical reactions in the mitochondrial matrix that completely oxidizes acetyl-CoA derived from carbohydrates, fats, and proteins. It produces CO₂, NADH, FADH₂, and ATP, connecting glycolysis to oxidative phosphorylation.
Key Points for NEET
- 1Occurs in mitochondrial matrix
- 2Starts with acetyl-CoA + oxaloacetate → citrate
- 3One turn produces: 3 NADH, 1 FADH₂, 1 GTP (ATP), 2 CO₂
- 4Oxaloacetate is regenerated (cycle)
- 5Also called citric acid cycle or TCA cycle
Example
Complete oxidation of glucose involves two turns of Krebs cycle (one per pyruvate)
Asked in NEET
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