Why does the citric acid cycle go around twice for each molecule?

The citric acid cycle goes around twice for each molecule of glucose that enters cellular respiration because there are two pyruvates—and thus, two acetyl s—made per glucose. Steps of the citric acid cycle You’ve already gotten a preview of the molecules produced during the citric acid cycle. But how, exactly, are those molecules made?

What is formed in the first step of the citrate cycle?

In the first step of the cycle, acetyl CoA\ext{CoA}CoAC, o, A combines with a four-carbon acceptor molecule, oxaloacetate, to form a six-carbon molecule called citrate.

How is oxaloacetate regenerated in the citric acid cycle?

In the last step of the citric acid cycle, oxaloacetate—the starting four-carbon compound—is regenerated by oxidation of malate. Another molecule of is reduced to in the process. Products of the citric acid cycle

How do you convert citrate to isocitrate step by step?

Step 1. Acetyl CoA combines with oxaloacetate in a reaction catalyzed by citrate synthase. This reaction also takes a water molecule as a reactant, and it releases a SH-CoA molecule as a product. Step 2. Citrate is converted into isocitrate in a reaction catalyzed by aconitase. Step 3.

Is phosphoenolpyruvate an intermediate in the citric acid cycle?

Phosphoenolpyruvate (PEP) is an intermediate in glycolysis, not the citric acid cycle. PEP is the product of the ninth reaction in glycolysis, which involves the enolase-catalyzed conversion of 2-phosphoglycerate into PEP.

How does NADH stop the citric acid cycle?

Ans: The citric acid cycle produces NADH, which normally is recycled by passage of electrons from NADH to O2 via the respiratory chain. With no O2 to accept electrons from NADH, the accumulation of NADH effectively stops the citric acid cycle.