A control point outside the citric acid cycle is the reaction catalyzed by
A) the pyruvate dehydrogenase complex.
B) citrate synthetase.
C) isocitrate dehydrogenase.
D) the a-ketoglutarate dehydrogenase complex.

Question

Quizplus · Accepted Answer

The pyruvate dehydrogenase complex catalyzes the conversion of pyruvate to acetyl-CoA, which is the entry point for the citric acid cycle. Therefore, it is a control point outside the citric acid cycle. Citrate synthetase, isocitrate dehydrogenase, and the alpha-ketoglutarate dehydrogenase complex are all enzymes that are part of the citric acid cycle and are not control points outside of it.

A Control Point Outside the Citric Acid Cycle Is the Reaction