Question

Although we study the citric acid cycle as the final stage oxidation of carbon from glucose, an in-depth look at the cycle shows intermediates entering and leaving the cycle from a number of metabolic pathways. With all of these demands on the cycle, how does it maintain a minimal level of oxaloacetate (OAA) to allow the cycle to function?A. Explain when GDP vs. ADP is used as a substrate with succinyl CoA synthetase.B. If 14C-labeled acetyl CoA is added to isolated mitochondria, is 14C-labeled CO2C. released in the first full cycle of the citric acid cycle? Explain your answer.D. Carbon monoxide is considered toxic because it acts on Complex IV. How wouldE. the addition of carbon monoxide to actively respiring mitochondria affect the relative oxidation-reduction states of all components of the electron-transport chain?F. Explain why less ATP is made from the reoxidation of FADH2 as compared to NADH.

Answer 1

-OAA can be formed by the condensation of two moles of acetyl CoA and occurs when the energy charge of the cell is high.

-The rate of the cycle is increased when the cell has high levels of NADH.

-Isocitrate dehydrogenase is allosterically inhibited by ADP, which signifies the need for more energy.

-OAA is formed directly via the deamination of glutamate.

-OAA is synthesized via pyruvate carboxylase in an anapleurotic reaction that occurs when acetyl CoA is present, such as from fatty acid breakdown

Step-by-step explanation: