ETC EXAM STUDY GUIDE
Based on what you see, what does DNP do? - Answers- The cyclist uses much more
glucose to maintain the same speed.
Describe the redox reaction that happens as electrons leave the NADH and jump onto
Complex I. - Answers- NADH is oxidized and Complex I is reduced.
How does the potential energy of electrons change as they move through the ETC? -
Answers- The potential energy of electrons decreases.
What do you notice about moving protons into the intermembrane space? - Answers-
As more protons are moved into the intermembrane space, it becomes harder to move
additional protons.
Why do you think it becomes harder to move each additional proton into the
intermembrane space? - Answers- Because as added protons make the
intermembrane space more positively charged, more energy is required to move
additional protons into that space.
As ATP is created, protons are moving back into the matrix through ATP synthase. What
happens to the potential energy of these protons? - Answers- Their potential energy is
transferred to ATP.
Which of the molecules below are necessary for the electrons from NADH to move all
the way to oxygen? - Answers- Complex 1
Cytosome c
Q
Complex III
Complex IV
Q2.8. The electrons' potential energy is highest when they are associated with: -
Answers- Complex I
The electrons' potential energy is lowest when they are associated with: - Answers-
Oxygen
Which molecules are needed for the electrons from FADH2 to move all the way to
oxygen? - Answers- Complex II
Q
Complex III
Cytochrome c
Complex IV
, Based on where the electrons from NADH and FADH2 enter the ETC, will energy stored
in NADH or in FADH2 result in the production of more ATP molecules? - Answers-
NADH
Which results in higher ATP production: NADH or FADH2? (Hint: You can count the ATP
molecules accumulated under ATP synthase.) - Answers- NADH
Energetically, what would happen if NADH transferred electrons directly to Complex II
(or later), instead of Complex I? - Answers- Fewer protons would be pumped, so less of
the energy stored in NADH would be transferred to ATP.
Why do you think FADH2 can't transfer electrons to Complex I? - Answers- Because
there is not as much potential energy stored in FADH2 compared to NADH.
Predict what will happen if no oxygen is available to the electron transport chain. -
Answers- ATP synthase will not be able to produce any ATP.
Initially, when the ETC is deprived of oxygen and you attempt to transfer electrons from
NADH and FADH2 to the ETC, what is the result? - Answers- There is not that much, if
any, of an immediate effect.
What happens to the ETC when oxygen is withheld for longer and you keep trying to
transfer electrons from NADH and FADH2 to the ETC? - Answers- Eventually, the ETC
cannot oxidize (i.e., accept electrons from) any additional NADH or FADH2.
What is the role of oxygen in the ETC? - Answers- Oxygen keeps the ETC running by
removing electrons from Complex IV.
Try to make an inference from the cyclist's behavior and her use of glucose and oxygen.
What is the effect of cyanide? - Answers- ATP production from glucose is reduced.
Which of the following is most similar to cyanide poisoning? - Answers- Oxygen
deprivation
Which of the following could be an effective treatment for severe cyanide poisoning? -
Answers- None of the above
Why might DNP be effective at causing weight loss? - Answers- People taking DNP
obtain less energy from each glucose molecule so they must "burn" more glucose than
they otherwise would.
What is the molecular mechanism of DNP? - Answers- DNP causes the inner
mitochondrial membrane to leak protons to the matrix.
Based on what you see, what does DNP do? - Answers- The cyclist uses much more
glucose to maintain the same speed.
Describe the redox reaction that happens as electrons leave the NADH and jump onto
Complex I. - Answers- NADH is oxidized and Complex I is reduced.
How does the potential energy of electrons change as they move through the ETC? -
Answers- The potential energy of electrons decreases.
What do you notice about moving protons into the intermembrane space? - Answers-
As more protons are moved into the intermembrane space, it becomes harder to move
additional protons.
Why do you think it becomes harder to move each additional proton into the
intermembrane space? - Answers- Because as added protons make the
intermembrane space more positively charged, more energy is required to move
additional protons into that space.
As ATP is created, protons are moving back into the matrix through ATP synthase. What
happens to the potential energy of these protons? - Answers- Their potential energy is
transferred to ATP.
Which of the molecules below are necessary for the electrons from NADH to move all
the way to oxygen? - Answers- Complex 1
Cytosome c
Q
Complex III
Complex IV
Q2.8. The electrons' potential energy is highest when they are associated with: -
Answers- Complex I
The electrons' potential energy is lowest when they are associated with: - Answers-
Oxygen
Which molecules are needed for the electrons from FADH2 to move all the way to
oxygen? - Answers- Complex II
Q
Complex III
Cytochrome c
Complex IV
, Based on where the electrons from NADH and FADH2 enter the ETC, will energy stored
in NADH or in FADH2 result in the production of more ATP molecules? - Answers-
NADH
Which results in higher ATP production: NADH or FADH2? (Hint: You can count the ATP
molecules accumulated under ATP synthase.) - Answers- NADH
Energetically, what would happen if NADH transferred electrons directly to Complex II
(or later), instead of Complex I? - Answers- Fewer protons would be pumped, so less of
the energy stored in NADH would be transferred to ATP.
Why do you think FADH2 can't transfer electrons to Complex I? - Answers- Because
there is not as much potential energy stored in FADH2 compared to NADH.
Predict what will happen if no oxygen is available to the electron transport chain. -
Answers- ATP synthase will not be able to produce any ATP.
Initially, when the ETC is deprived of oxygen and you attempt to transfer electrons from
NADH and FADH2 to the ETC, what is the result? - Answers- There is not that much, if
any, of an immediate effect.
What happens to the ETC when oxygen is withheld for longer and you keep trying to
transfer electrons from NADH and FADH2 to the ETC? - Answers- Eventually, the ETC
cannot oxidize (i.e., accept electrons from) any additional NADH or FADH2.
What is the role of oxygen in the ETC? - Answers- Oxygen keeps the ETC running by
removing electrons from Complex IV.
Try to make an inference from the cyclist's behavior and her use of glucose and oxygen.
What is the effect of cyanide? - Answers- ATP production from glucose is reduced.
Which of the following is most similar to cyanide poisoning? - Answers- Oxygen
deprivation
Which of the following could be an effective treatment for severe cyanide poisoning? -
Answers- None of the above
Why might DNP be effective at causing weight loss? - Answers- People taking DNP
obtain less energy from each glucose molecule so they must "burn" more glucose than
they otherwise would.
What is the molecular mechanism of DNP? - Answers- DNP causes the inner
mitochondrial membrane to leak protons to the matrix.
