George Mason University The Citric Acid Cycle Biochemistry Quiz

I need help with biochemistry quiz. I have attached the lecture slides.

Quiz questions

1- The oxidative decarboxylation of pyruvate is a highly exergonic reaction. How is the energy released by this reaction conserved?

2- The concentration of oxaloacetate in the cell is normally quite low. What factor in the citrate synthase reaction prevents this from hindering the operation of the cycle?

3- What is the source of the energy used to drive the substrate-level phosphorylation of GDP in the reaction catalyzed by succinyl-CoA synthetase? What are the difference between substrate-level phosphorylation and respiration-linked phosphorylation?

4- What is the net energy yield per molecule of glucose for the combined reactions of glycolysis, the pyruvate dehydrogenase reaction, and the citric acid cycle?