ETC Flashcards
The negative reducing potential says that
The more negative an entity, the greater its tendency to donate electrons.
The positive reducing potential says that
The more positive an entity, the greater its tendency to accept electrons.
Name the five compound carriers involved in the ETC
- NAD+/NADH
- FAD/FADH2
- Ubiquinone
- iron-sulfur centers
- cytochromes
Which compound is not an electron carrier involved in the respiratory chain?
A. NADH
B. Iron-sulfur proteins
C. Cytochrome
D. Coenzyme A
D
Describe what happens in complex I of the ETC
NADH passes its electrons (one at a time) onto complex I in which a flavoprotein (FMN) is going to accept them. FMN transfers the electrons through a series of iron-sulfer centers all the way up to Q. Q accepts the electrons to become QH2.
In the meantime, protons are also pump into the intermediate space.
Note: QH2 passes electrons onto complex III
Describe what happens in complex II of the ETC
FADH2 transfers its electrons onto complex II in which they are passed through a series of iron-sulfer centers all the way to Q to reduce it to QH2.
Note: QH 2 passes electrons onto complex III
What are two names associated with complex I
NADH ubiquinone oxidoreductase or NADH dehydrogenase
What is the name of complex II
succinate dehydrogenase
Which complex is the only one that does not pump electrons?
complex II
Describe what happens in complex III of the ETC
QH2 is oxidized and the electrons are transferred through a series of iron-sulfer centers and cytochromes all the way to cytochrome C which is then reduced. Cytochrome C passes the electrons onto complex 4.
Describe what happens in complex IV of the ETC
Cytochrome oxidase picks up the electrons from cytochrome C and passes them onto molecular O2. O2 then picks up protons to form H2O.
