CELL RESPIRATION
THE KREBS CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It is oxidized to form acetyl Co-A
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It reduces coenzyme A
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It is reduced to form citric acid
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It oxidizes ATP
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Detailed explanation-1: -A carboxyl group is removed from pyruvate and released as carbon dioxide. The two-carbon molecule from the first step is oxidized, and NAD+ accepts the electrons to form NADH. The oxidized two-carbon molecule, an acetyl group, is attached to Coenzyme A to form acetyl CoA.
Detailed explanation-2: -Before the Krebs cycle begins, pyruvate, which has three carbon atoms, is split apart and combined with an enzyme known as CoA, which stands for coenzyme A. The product of this reaction is a two-carbon molecule called acetyl-CoA.
Detailed explanation-3: -In the conversion of pyruvate to acetyl CoA, each pyruvate molecule loses one carbon atom with the release of carbon dioxide. During the breakdown of pyruvate, electrons are transferred to NAD+ to produce NADH, which will be used by the cell to produce ATP.
Detailed explanation-4: -Technically, pyruvate oxidation includes the Krebs cycle because the product of pyruvate oxidation (acetyl CoA) is further oxidized into more carbon dioxide.
Detailed explanation-5: -In Summary: Pyruvate Oxidation In the presence of oxygen, pyruvate is transformed into an acetyl group attached to a carrier molecule of coenzyme A. The resulting acetyl CoA can enter several pathways, but most often, the acetyl group is delivered to the citric acid cycle for further catabolism.