5. Regulation of oxidative phosphorylation Consider a liver cell carrying out th

Question

5. Regulation of oxidative phosphorylation Consider a liver cell carrying out the oxidation of glucose under aerobic conditions. Suppose that we added a very potent and specific inhibitor of the mitochondrial ATP synthase, completely inhibiting this enzyme (e.g., oligomycin). Indicate whether each of the following statements about the effect of this inhibitor is true or false; if false, explain in a sentence or two why it is false. (a) The rate of oxygen consumption will increase (b) The citric acid cycle will speed up to compensate.

Explanation / Answer

a. FALSE because Because electron transfer through the respiratory chain is tightly coupled to ATP synthesis, blocking ATP synthase blocks electron flow and oxygen consumption.

b. FALSE Because The citric acid cycle is an oxidative pathway, producing NADH. When electron flow from NADH to O2 is blocked, NADH accumulates, NAD+ is depleted, and the citric acid cycle slows for lack of an electron acceptor (NAD+).

Related Questions

Navigate

• Browse (All)
• Browse 5
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.