Reading Guide, Pratt and Cornely Chapter 15
1. What is the difference between oxidative phosphorylation and substrate level phosphorylation/
2. Reduction potential indicates a substance’s tendency to ______________________.
3. A negative standard reduction potential means that a compound will _______________
(spontaneously/not spontaneously) accept electrons under standard conditions.
4. According to the Nernst equation, the actual reduction potential of a reaction under cellular
conditions depends on its _____________ and ___________.
5. A compound with a lower (more negative) reduction potential will tend to ___________
(donate/accept) electrons to/from a compound with a higher (more positive) reduction potential.
6. Use table 15-1 to calculate the standard reduction potential when acetate donates two electrons
to NAD+.
7. A reaction with a larger positive change in reduction potential will be (more/less) spontaneous.
8. Define respiration.
9. Why are electrons are shuttled from NADH to molecular oxidation in several steps rather than
one?
10. Draw a schematic of a mitochondrion and label the membranes and spaces.
11. Most NADH is made in the ____________ of the mitochondria. NADH made in the cytosol
are not taken directly into the mitochondria, but reducing equivalents are transported in through
the ______________________ shuttle.
12. Complex I catalyzes transfer of high energy electrons from _____________ to
____________ through a series of redox centers.
13. Why is it important that the standard redox potential of the redox centers of Complex 1 have
values between -0.315 V and +0.045 V?
14. How many electrons can be carried by NADH, FMN, iron-sulfur clusters, and Q? How many
electrons can be donated/accepted at one time by NADH, FMN, iron-sulfur clusters, and Q?
15. How many protons are channeled through Complex I when two electrons are donated from
NADH? The protons don’t travel through a channel; rather, they are pass through a
“_______________.”
16. Complex II, also called ___________________ from the citric acid cycle, adds to the pool of
_________________ but does not transport any protons.
17. Complex III transports ____ protons by passing electrons from QH2 to
___________________, which contain heme groups. This pathway allows for more protons to
shuttle through because of a complicated process call the _________________.
18. The ultimate electron acceptor for Complex IV is ____________.
19. In complex IV, the total number of protons depleted in the matrix is 4, 2 through
___________________ and 2 through _________________.
20 How is the potential energy of NADH electrons “stored” through the respiration process?
21. The protonmotive force is comprised to two terms, representing the potential difference of
____________________ and ______________.
22. Draw a simple schematic of ATP synthase in terms of its F0 and F1 components. What is the
main function of each component?
23. On a chemical level, how does a proton gradient cause a motor to turn?
24. Describe ATP synthesis in terms of the binding change mechanism. Use the terms “loose”,
“tight,” and “open.”
25. What is an uncoupling agent, and why is it toxic? How is uncoupling a good thing in
hibernation?
26. What is meant by P:O ratio? What is the in vivo P:O ratio for NADH oxidation in mammals?