In going from acetyl-coa to succinate, two carbons have entered the cycle and two have been released as co 2. why is the cycle not considered as complete at this point?

The correct answer will be- the oxaloacetate regeneration proceeds the acetyl CoA to succinate steps.

Explanation:

The citric acid cycle takes place during cellular respiration which helps the synthesis of the reducing equivalents utilized during the electron transport chain.

The Citric acid cycle begins when the carbon from the acetyl CoA is transferred to the four-carbon compound called oxaloacetate which gets converted to the citrate. Further conversions convert the citrate to the succinate during which entered carbon exits as CO₂.

But the cycle is not complete as the oxaloacetate which accepts the carbon is not regenerated and the regeneration step takes place after the formation of succinate.

Thus, the oxaloacetate regeneration proceeds the acetyl CoA to succinate steps is the correct answer.