Practice Exam 2 Flashcards
The _____ cycle feeds electrons into Complexes I and II in the mitochondria, while the ______ cycle uses high energy electrons, which have been stored upon their exit from photosystem I.
carbon-fixation; citric acid
citric acid; Q
Q; carbon-fixation
citric acid, carbon-fixation
carbon-fixation; Q
citric acid, carbon-fixation
The potential energy stored by chloroplasts, in the form of ATP and NADPH, is most directly used to:
drive the dark reactions.
fuel ATP dependent reactions all over the cell.
create a proton gradient.
split water.
transport ADP into mitochondria
drive the dark reactions.
NADH dehydrogenase is a _____ electron acceptor, while NADH is a _____ electron donor. O2 is a _____ electron acceptor.
strong; weak; weak
weak; strong; strong
weak; weak; strong
strong; weak; strong
weak; strong; weak
weak; strong; strong
Electrons exit the light reactions of photosynthesis with a more negative redox potential than when they started, and electrons exit the mitochondrial electron transport chain with a more _____ redox potential than when they started.
Negative
Neutral
Positive
Positive
The high membrane curvature of the cristae structure is physically supported and enabled by: (1. ATPase dimers; 2. Phosphatidylcholine; 3. Enzymes of the electron transport chain; 4. Proton gradient; 5. Cardiolipin)
3 & 4
2 & 3
1 &2
1 &5
4 & 5
1 &5
The mitochondrial space that accumulates electron transport chain (ETC)-pumped-protons is the:
Matrix
Cristae space
Intermembrane space
Mitochondrial adjacent cytosol
Nuclear envelope
Cristae space
Only mitochondria with a functional _____ undergo _____.
electrochemical gradient; fusion
ATP synthase; fission
Electrochemical gradient; fission
ATP synthase; fusion
Electron transport chain, fission
electrochemical gradient; fusion
Which of the following is FALSE? Redox pairs when measured against a proton/hydrogen gas standard are:
negative if electrons move to the standard.
positive if electrons move to the redox pair.
zero if electrons do not move.
All of the choices are true.
All of the choices are false.
All of the choices are true.
What is the change in free energy when two electrons move from ubiquinone (+30 mV) to cytochrome C (+230 mV).
200 mV
38.4 kJ/mole
-19.2 kJ/mole
-38.4 kJ/mole
-76.8 kJ/mole
-38.4 kJ/mole
Which of the following lists describes mitochondrial Q electron carriers becoming increasingly reduced going left to right.
Ubiquinone, Ubiquinol, Ubisemiquinone
Ubisemiquinone, Ubiquinol, Ubiquinone
Ubiquinol, Ubisemiquinone, Ubiquinone
Ubiquinone, Ubisemiquinone, Ubiquinol
Ubiquinol, Ubiquinone, Ubisemiquinone
Ubiquinone, Ubisemiquinone, Ubiquinol
There are two places where electrons can enter the mitochondrial electron transport chain. Where do their paths first converge?
NADH dehydrogenase
Q
Succinate dehydrogenase
O2
Cytochrome C oxidase
Q
Within NADH dehydrogenase, the _____ arm gathers energy and funnels it, in the form of a changed protein conformation, to the membrane arm where proton wires become _____.
matrix; blocked
cristae; blocked
matrix; aligned
intermembrane; aligned
intermembrane; blocked
matrix; aligned
Which of the following results in the most ATP produced?
Oxidation of a glucose molecule in the cytosol.
Oxidation of a glucose molecule in the mitochondria.
Oxidation of a palmitate molecule in the mitochondria.
Oxidation of a palmitate molecule in the mitochondria.
The mitochondrial ATP synthase is like the ATP synthase it which other structure?
Thylakoid membrane
Bacterial inner membrane
Archaeal inner membrane
All of the choices
None of the choices
All of the choices
About how many protons passing down their electrochemical gradient are required to make one molecule of ATP with the ATPase rotor shown here?
1-2
4-5
13-14
26
52
4-5