Answer: 4
Step-by-step explanation:
Krebs cycle, also known as the TCA (tricarboxylic acid) or citric acid cycle, takes place inside the mitochondrial matrix. This cycle is a stepwise oxidative and cyclic degradation of acetyl CoA. The cycle acts on the 2 pyruvate molecules generated during glycolysis.
The end product of glycolysis is pyruvate. 1 molecule of glucose produces 2 molecules of pyruvate. So 1 molecule of pyruvate is responsible for the release of 2 CO2 molecules during 1 Krebs cycle. Since 1 glucose molecule gives 2 pyruvate molecules. There will be two cycles to utilize both the pyruvate molecules. Thus, 1 glucose molecule is responsible for the release of 4 CO2 molecules during Krebs cycle.
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