Quiz 2

ATP synthesis in mitochondrion is driven by energy produced in electron
transport pathway. And this energy is stored in the form of ________. ATP synthesized in this process is called _____ hosphorylation.
ATP produced in TCA cycle is called ______ phosphorylation.

Which of the following step does NOT produce NADH?

All the enzymes in the TCA cycle are water soluble and located in the matrix
of mitochondrion. True or False.
True False

Pyruvate dehydrogenase is regulated by which covalent modification?

The precise mechanism of NADH-UQ reductase is unknown, but the electron
transport involves...

Which complex is not coupled with proton translocation in electron
transport pathway _______.

The components of electron transport chain include two mobile electron
carriers, a lipid-soluble molecule _________ and a water-soluble protein __________.

Which of the following enzyme is not allosterically inhibited by high level of
NADH?

Please write down the coenzymes involved in the reaction: pyruvate -------> acetyl-CoA.

The terminal electron acceptor in eukaryotic aerobes is _______.

If the F0 unit of ATP synthase has the stoichiometry of a1b2c12, How many
degrees of rotation of one of the c subunits relative to the a subunit occur
with each proton transferred to the matrix?

Which enzyme in the citric acid cycle proceeds by a similar mechanism and
with similar cofactors as pyruvate dehydrogenase?

Q cycle is a unique redox pathway in ______.

Which complex of the electron transport chain does not contain a
cytochrome?

The electron transfer in complex IV is from cytochrome c to _____ to
heme a, then to ________ and in the end to O2.

The energy-requiring step of ATP synthesis in ATP synthase is the release of ATP. True or False.
True False

Electron transport causes the proton translocation of protons across the
inner membrane of mitochondria. What compartment has a lower pH?

The glycerophsophate shuttle and ________ shuttle feed the electrons from _______ into electron transport in mitochondrion.

In your own words, please describe the purpose of TCA cycle in two or three
sentences. Please be brief and you don’t have to go into details of the
reactions

Please draw the pathway how the electrons from NADH are transferred to
O2. Write down the full names of the complexes.

Please write down the reaction(s) that produces GTP in TCA cycle. Include
the enzymes (coenzymes) and the structures of the substrates and products.
And write down an intermediate (structure/name) during catalysis.

For each acetate oxidized, the net outcome of the TCA cycle is...

Which enzyme in the citric acid cycle catalyzes the reaction that directly produces a high-energy nucleoside triphosphate?

Place these substrates in the correct sequence for the TCA cycle.
a. isocitrate
b. succinyl-CoA
c. fumarate
d. malate

Pyruvate carboxylase catalyzes the most important anaplerotic reaction which is.....

Both fumarase and aconitase catalyze the addition of the elements of water across a double bond. This addition is:

In the isomerization of citrate to isocitrate, the intermediate is:

Which reaction of the TCA cycle catalyzes a substrate-level phosphorylation?

Place these enzymes in the correct sequence for the TCA cycle:

The three main regulatory sites in the TCA cycle are:

Which of the following is not true concerning citrate synthase?

Which enzyme of the TCA cycle is an integral membrane protein?

Pyruvate dehydrogenase (PDH) is regulated by covalent modification. The PDH kinase phosphorylates and inactivates PDH. The PDH kinase is allosterically activated by a low:

Which of the following enzymes catalyzes an anaplerotic reaction for the TCA cycle?

The oxidative decarboxylation of pyruvate to acetyl-CoA is catalyzed by:

Which enzyme in the citric acid cycle proceeds by a similar mechanism and with similar cofactors as pyruvate dehydrogenase?

The succinate dehydrogenase reaction is stereospecific. The mechanism involves the removal of:

The essential feature of thiamine pyrophosphate chemistry is:

The chemiosmotic coupling hypothesis proposed by Peter Mitchell states that:

The flow of electrons through complex IV is:

Which of the following electron carriers is the most mobile?

Which of the following is not an inhibitor of complex I, II, or III?

Which of the following electron carriers participates in both one and two electron transfers?

The malate –aspartate shuttle transfers 2e- from:

Which of the following cytochromes of the electron transport chain is NOT tightly bound to an integral membrane protein?

Oligomycin is a macrocyclic antibiotic that inhibits oxidative phosphorylation. It....

Proton transfer through the Fo subunit of ATP synthase causes a:

Where are most of the processes of electron transport and oxidative phosphorylation localized in eukaryotes?

In EACH of the two steps of the Q-cycle, when fully reduced coenzyme Q, QH2, is re-oxidized by complex III:
a. one e- is transferred to cytochrome c1
b. one e- is transferred to the bL heme
c. two H+ are released on the cytosolic side of the membrane
d. one H+ is taken up on the matrix side of the membrane
e. one e- is transferred from the Qp site on the matrix side to the Qn site on the cytosolic side of the membrane

If the Fo unit of ATP synthase has the stoichiometry of a1b2c9, how many degrees of rotation of one of the c subunits relative to the α subunit occur with each proton transferred to the matrix?

Which of the following is true about the flavoprotein complexes?
a. they are all sites where protons are transferred across the inner mitochondrial membrane
b. they all contain FMN
c. they all contain FAD
d. they all contain Fe-S centers
e. they all transfer electrons to UQ

Which of the following are true?
a. the glycerophosphate shuttle and the malate-aspartate shuttle yield the same number of ATP's starting from NADH in the cytosol
b. the glycerophosphate shuttle yields the same number of ATP's per 2 electrons donated as complex II of the electron transport chain
c. the malate-aspartate shuttle is more energy efficient than the glycerophosphate shuttle
d. the glycerophosphate shuttle can donate electrons to the electron transport chain even when the cytosolic [NADH] is low
e. the malate-aspartate shuttle is essentially irreversible

The terminal electron acceptor in eukaryotic aerobes is:

Which complex of the electron transport chain does not contain a cytochrome?

Dinitrophenol, a hydrophobic weak acid with a pKa of 9, is an uncoupler of oxidative phosphorylation. It:

Which of the following is a mobile, lipid-soluble electron carrier found in the inner mitochondrial membrane?