Please explain why as well. (For some I know the answers but need an explanation
ID: 271938 • Letter: P
Question
Please explain why as well. (For some I know the answers but need an explanation)
1. Cytochrome C is responsible for
A. Transfer of electrons between complexes I & II
B. Movement of protons out of the mitochondria and into the cytosol
C. Transfer of electrons between complexes III & IV
D. Uncoupling ATP synthesis from the electron transport chain E. None of the above
7. Which of the following statement(s) about 2,4-dinitrophenol (DNP) is/are TRUE?
A. It is a hydrophobic compound
B. It uncouples electron transport from ATP synthesis
C. It diffuses through the inner mitochondrial membrane
D. It binds to protons
E. All of the above
8. Which of the following inhibitor(s), when used on isolated mitochondria, is/are likely to maintain/keep complex III in an oxidized state?
A. Rotenone
B. Cyanide
C. Azide
D. Carbon monoxide
E. A & B
F. A & C
G. B & D
H. C & D
9.A mutation in complex II would be expected to impair electron transport from which compound below?
A. Alpha-ketoglutarate
B. Succinate
C. Malate
D. Isocitrate
E. Acetyl-CoA
10. From the list below, choose the ONE site or step along the ETC that is not coupled to ATP synthesis.
A. Succinate to Coenzyme Q
B. NADH to Coenzyme Q
C. Coenzyme Q to Cytochrome C
D. Cytochrome C to O2
11. How does oligomycin work?
A. It is an uncoupler of oxidative phosphorylation
B. It inhibits NADH dehydrogenase
C. It blocks the flow of protons through F0
D. It is an inhibitor of cytochrome oxidase
Explanation / Answer
1)answer is option C
Cytochrome C is responsible for electrons transport between complex-3 and complex-4.
Complex-3- cytochrome bc1(ubiquinol-cytochrome c reductase)
Complex-4-cytochrome c oxidase
Due to energy gradient electrons move from comples-3 to-4.
9)answer is option B
succinate dehydrogenase is the complex-2 in electron transport chain.which is mutated by the given conditions.
So the compound succinate is affected by mutation.
10)answer is option A
Succinate to co enzyme Q
As in the other steps when electrons pass through them there is proton pumping into intermembrane space. So directly linked to atp synthesis by ATP synthase.
But in succinate to co enzyme Q there is only transport of electrons but no proton pumping is seen into intermembrane space.
11)oligomycin is a macrolide created by streptomyces.
It is inhibitor for ATP SYNTHASE.
It inhibits by blocking proton channel.that is by blocking F0 subunit.so that proton flow is blocked by it.
Answer is option C.