Oxidative Phosphorylation & ATP Synthesis (9.5)

23 questions β€’ 1 test β€’ tap a section to begin

Welcome! Oxidative Phosphorylation & ATP Synthesis (9.5) — 23 questions across 1 tests.

How the tests are arranged

  • Test 1 (9.5) — Oxidative Phosphorylation & ATP Synthesis

How to use

  • Tap any test below — it opens on its own full screen. Use ← All tests at the top to come back.
  • Answer the questions, then Submit to see your score.
  • Tap πŸ“‹ View Solution under any question for a full explanation.

Open Review at the bottom for a quick revision list of every question with its correct answer.

Quiz
Question Palette
Quiz
Question Palette
Quiz
Explanation:

Quick revision: every question with its correct answer. For the full explanation, open the relevant test and tap View Solution.

9.5 Oxidative Phosphorylation β€” Test 1
Q1. F0F1 ATP synthase can best be described as a:βœ“ Molecular motor
Q2. F0F1 ATP synthase is best described as:βœ“ A molecular motor / rotary enzyme
Q3. Assertion: ATP synthase is not part of the electron transport chain. Reason: ATP synthase is coupled to the ETC through the proton-motive force.βœ“ Both true and the reason correctly explains the assertion
Q4. ATP biosynthesis using an H⁺ gradient occurs across which membranes?βœ“ Inner mitochondrial membrane and thylakoid membrane of chloroplast
Q5. The proton electrochemical free energy is Ξ”G = 2.303 RT log([H⁺]out/[H⁺]in) + nFψ. If protons were uncharged, the equation becomes:βœ“ 2.303 RT log([H⁺]out/[H⁺]in)
Q6. Which combination of agents would completely destroy the electrochemical proton potential across the inner mitochondrial membrane? I) Valinomycin (K⁺ ionophore), II) Nigericin (K⁺/H⁺ antiporter), III) Rotenone, IV) Oligomycin.βœ“ I and II
Q7. Approximately how many ATP are generated by oxidation of one mole of FADHβ‚‚ in an actively respiring mitochondrion?βœ“ 1.5
Q8. The H⁺/ATP ratios of chloroplast and mitochondrial F0F1 ATP synthases are approximately in the order of:βœ“ 4.7 and 3.3
Q9. The H⁺/ATP ratio of chloroplast and mitochondrial F0F1 ATP synthases is approximately (variant):βœ“ 4.7 and 3.3
Q10. How many ATP are generated from oxidation of one NADH (entering at Complex I) during electron transport?βœ“ 2.5
Q11. The number of ATP generated following oxidation of one molecule of NADH during electron transport is about:βœ“ 2.5–3
Q12. Oxidative phosphorylation refers to:βœ“ Production of ATP by chemiosmosis (using the ETC proton gradient)
Q13. The P:O ratio is a measure of how many moles of ATP are formed from ADP per:βœ“ Atom of oxygen for a given substrate
Q14. Estimate the free energy to translocate one proton OUT of the matrix when pH_matrix = 7.8, pH_cytosol = 7.15, ΔΨ = 170 mV, T = 25Β°C. The value is approximately:βœ“ +20.1 kJ/mol
Q15. How does the proton-motive force differ between mitochondria and chloroplasts?βœ“ In mitochondria the electrical gradient (ΔΨ) contributes more; in chloroplasts the pH gradient (Ξ”pH) contributes more
Q16. Which statement correctly contrasts the proton-motive force in mitochondria vs chloroplasts?βœ“ Mitochondria: electrical gradient contributes more; chloroplast: proton (pH) gradient contributes more
Q17. Which is a balanced equation for the Q-cycle of the cytochrome b6f complex of chloroplasts?βœ“ PQHβ‚‚ + 2H⁺(stroma) + 2 PC(Cu²⁺) β†’ PQ + 2 PC(Cu⁺) + 4 H⁺(thylakoid)
Q18. Which cell component contains Uncoupling Protein 1 (UCP1, thermogenin)?βœ“ Mitochondria of brown adipose tissue
Q19. Adding valinomycin (with K⁺) to actively respiring mitochondria dissipates:βœ“ The electrical potential (ΔΨ)
Q20. The more negative the standard reduction potential of a redox pair, the greater its tendency to:βœ“ Lose an electron (act as a reducing agent)
Q21. Cyanide poisoning causes death because it disrupts:βœ“ The heme protein cytochrome c oxidase
Q22. Which compound acts as an uncoupler in oxidative phosphorylation?βœ“ 2,4-dinitrophenol
Q23. In brown adipose tissue, thermogenin (UCP1) causes:βœ“ Uncoupling of phosphorylation from electron transfer