1.
Superoxide dismutase protects cells from damage caused by
A
B
-
C
D
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Superoxide dismutase protects cells from damage caused by
-
The terminal electron acceptor for complex III of the electron transport chain is
Fe-S
Q
FAD
cytochrome C
Which complex in the electron transport chain does not contribute to the proton gradient?
I
II
III
IV
How many protons are translocated across the membrane by complex I for every pair of electrons that are passed from NADH to QH2?
1
2
3
4
Which is a component of complex I?
FMN
FAD
TPP
Q
To reduce one molecule of , ..............electron(s) must be passed through the electron transport chain and ..............molecule(s) of NADH is(are) oxidized.
1, 1
4, 4
1, 2
4, 2
Which has the highest reduction potential?
complex I
complex II
NADH
What feature of cytochromes makes them valuable in electron transport systems?
aspartate residues in the active site
the multiple alpha-helices
the porphyrin ring
the iron ion
At one time the uncoupler 2, 4-dinitrophenol was used as a weight reducing drug. Its side-effects, including death, resulted in its discontinued use. How could this drug cause weight loss?
The uncoupler is an allosteric activator of ATP synthase. This increases the rate of translocation of H+ and the oxidation of fuels, including fats.
The uncoupler allows the oxidation of fats from adipose tissue without the production of ATP. This allows the oxidation to proceed continuously and use up the fats.
The uncoupler inhibits the transport of pyruvate into the matrix of the mitochondria. Fats are then degraded to glycerol and subsequently to pyruvate to provide the necessary energy. Thereby depleting fat stores.
The uncoupler causes ATP to be produced at a much higher rate than normal and this causes weight loss.
The protonmotive force is a result of
the flow of protons within the inner mitochondrial membrane
a combination of an electrical potential and a chemical potential
the flow of electrons from the matrix to the inner membrane space
All of the above
The chemiosmotic theory is a concept that
the transport of Na+ and K+ across cell membranes is by active transport
explains how transport by facilitated diffusion reaches a saturation limit
a proton gradient that drives the formation of ATP
explains the blood-brain barrier
The inner mitochondrial membrane contributes to the formation of a proton gradient mainly because it
is rich in proteins.
is not rich in proteins.
is the location of specific transporter proteins.
is a barrier to protons.
ATP synthase is located in the...................of the mitochondrion.
intermembrane space
outer membrane
matrix
inner membrane
Oxidative phosphorylation requires all of the items listed below except
the flow of electrons from NADH and in the membrane.
a matrix more positively charged than the intermembrane space.
a terminal electron acceptor which is in mitochondria.
ATP synthase in the correct position in the membrane.
The................is between the inner and outer membranes of the mitochondria.
ATP synthase complex
intermembrane space
matrix
intracellular fluid
In the mitochondria NADH and QH2 are essentially oxidized by ...............since it is the terminal electron acceptor.
carbon dioxide
ozone
hydrogen peroxide
oxygen