Q2. The release of ATP by the beta subunit is most directly dependent on: Select
ID: 260159 • Letter: Q
Question
Q2.
The release of ATP by the beta subunit is most directly dependent on:
Select ONE option:
1. the flow of protons from the intermembrane space to the matrix.
2. the rotation of the c-ring in the membrane.
3. the passage of electrons along the electron transport chain.
4. a conformational change in the beta subunit.
Q3.
What defines the direction of rotation of the c-ring in the F0 complex?
(Select ALL that apply.)
1. Amino acids side chains in c-subunits will repel a bound proton if the c-ring rotates in the wrong direction
2. The availability of ADP and inorganic phosphate as substrates
3. The direction of the proton gradient relative to the inner mitochondrial membrane
4. The conformational changes in the alpha and beta subunits
Q4.
The release of protons by the c-ring is more favorable on the matrix side of the membrane because:
Select ONE option:
1. of the lower concentration of protons on the matrix side.
2. of the rotation of the c-ring.
3. ATP is synthesized on the matrix side.
4. the citric acid cycle enzymes are on the matrix side.
Q5.
By which of the following mechanisms could ATP synthesis potentially be inhibited?
(Select ALL that apply.)
A. By dissociating the F1 complex from the F0 complex
B. By blocking proton passage through the F0 complex
C. By blocking the rotation of the ?3?3 hexamer of the F1 complex
D. By blocking inorganic phosphate from binding to the F1 complex
Q6.
What would happen to the mitochondrial proton gradient, mitochondrial respiration (mitochondrial oxygen consumption), and the NADH oxidation rate in cells treated with carbonyl cyanide-4-trifluoromethoxyphenylhydrazone (FCCP), a molecule that increases the permeability of the inner mitochondrial membrane to protons?
Part 1. The mitochondrial proton gradient would:
Select ONE option:
1. increase
2. decrease
Part 2. Mitochondrial respiration (mitochondrial oxygen consumption) would:
Select ONE option:
1. increase
2. decrease
Part 3. The NADH oxidation rate would:
Select ONE option:
1. increase
2. decrease
Explanation / Answer
Answer. 2 (1) the flow of proton from the intermembrane space to matrix. As proton help in releasing of ATP.
Answer 3. (3 and 4) as c ring rotation depends upon both alpha and beta subunit and proton gradient.
Answer 4. (1) as proton release by c ring is more favorable in case of lower concentration of proton on matrix side.
Answer 5 all implies as ATP synthesis is inhibited in every situation given in options. As proton is the main rotational factor. If Fo-F1 particle dissociate then there is no proton transportation and no ATP synthesis of we block alpaha and beta subunit then there is no rotation. And there is no ATP released. Also If inorganic phosphate can not bind to F1 subunit still there is no ATP production as binding of inorganic phosphate to ADP causes in ATP synthesis.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.