BMSC 230- Module 7,8,10-Questions
with Solved Solutions.
Oxidative Phosphorylation - Answer The production of ATP using energy derived from the
redox reactions of an electron transport chain; the third major stage of cellular respiration.
Electron-transport chain - Answer A sequence of electron carrier molecules (membrane
proteins) that shuttle electrons during the redox reactions that release energy used to make
ATP.
Cellular respiration - Answer Collective activities of the citric acid cycle and oxidative
phosphorylation, ultimately regulated by the need for ATP
Reduction potential (E0') - Answer the inherent tendency, measured in volts under standard
conditions, of a compound to donate electrons
Flavin mononucleotide - Answer Enzyme which oxidizes NADH
Iron-sulfur (nonheme-iron) protein - Answer Proteins that contain clusters of iron and sulfur
that play a role in electron-transfer reactions; iron cycles between the Fe2+ and Fe3+ state
Cytochromes - Answer An iron-containing protein that is a component of electron transport
chains in the mitochondria and chloroplasts of eukaryotic cells and the plasma membranes of
prokaryotic cells
Coenzyme Q (Ubiquinone) - Answer A small non-protein electron carrier in the electron
transport chain.
Q pool - Answer A pool of coenzyme Q (Q) and ubiquinol (QH2) thought to exist in the inner
mitochondrial membrane. Because ubiquinone is soluble in the hydrophobic interior of the
membrane, the components of the Q pool can readily shuttle between the larger electron
carriers in the membrane.
Complex I - Answer NADH-Q oxidoreductase
Complex II - Answer Succinate-Q reductase
Complex III - Answer Q-cytochrome c oxidoreductase
, NADH-Q Oxidoreductase - Answer integral membrane protein proton pump, reduces Q
Succinate-Q reductase - Answer An integral-membrane-protein complex of the inner
mitochondrial membrane that transfers electrons from FADH2FADH2 formed in the citric acid
cycle to coenzyme Q
Q-cytochrome c oxidoreductase - Answer A component of the respiratory chain, this
oxidoreductase carries electrons from coenzyme Q to cytochrome c and, in the process, pumps
protons out of the mitochondrial matrix to generate the proton-motive force.
Complex IV - Answer cytochrome c oxidase
Cytochrome C oxidase - Answer The final complex of the respiratory chain, it transfers
electrons from cytochrome c to molecular oxygen and concomitantly pumps protons across the
inner mitochondrial membrane to generate the proton-motive force
Cytochrome c - Answer Involved in energy transfer, it is a protein released from mitochondria
when cell is stressed.
Q cycle - Answer The shuttling of electrons between ubiquinol and ubiquinone in the inner
mitochondrial membrane as a part of Complex III's function
Respirasome - Answer moves electrons from ubiquinol (QH2) to oxygen
Superoxide dismutase - Answer catalyzes conversion of superoxide radicals to hydrogen
peroxide
Catalase - Answer An enzyme produced in all cells to decompose hydrogen peroxide, a by-
product of cell respiration
Complex V - Answer ATP synthase
ATP synthase - Answer Large protein that uses energy from H+ ions to bind ADP and a
phosphate group together to produce ATP
Proton-motive force - Answer The potential energy stored in the form of an electrochemical
gradient, generated by the pumping of hydrogen ions across biological membranes during
chemiosmosis.
with Solved Solutions.
Oxidative Phosphorylation - Answer The production of ATP using energy derived from the
redox reactions of an electron transport chain; the third major stage of cellular respiration.
Electron-transport chain - Answer A sequence of electron carrier molecules (membrane
proteins) that shuttle electrons during the redox reactions that release energy used to make
ATP.
Cellular respiration - Answer Collective activities of the citric acid cycle and oxidative
phosphorylation, ultimately regulated by the need for ATP
Reduction potential (E0') - Answer the inherent tendency, measured in volts under standard
conditions, of a compound to donate electrons
Flavin mononucleotide - Answer Enzyme which oxidizes NADH
Iron-sulfur (nonheme-iron) protein - Answer Proteins that contain clusters of iron and sulfur
that play a role in electron-transfer reactions; iron cycles between the Fe2+ and Fe3+ state
Cytochromes - Answer An iron-containing protein that is a component of electron transport
chains in the mitochondria and chloroplasts of eukaryotic cells and the plasma membranes of
prokaryotic cells
Coenzyme Q (Ubiquinone) - Answer A small non-protein electron carrier in the electron
transport chain.
Q pool - Answer A pool of coenzyme Q (Q) and ubiquinol (QH2) thought to exist in the inner
mitochondrial membrane. Because ubiquinone is soluble in the hydrophobic interior of the
membrane, the components of the Q pool can readily shuttle between the larger electron
carriers in the membrane.
Complex I - Answer NADH-Q oxidoreductase
Complex II - Answer Succinate-Q reductase
Complex III - Answer Q-cytochrome c oxidoreductase
, NADH-Q Oxidoreductase - Answer integral membrane protein proton pump, reduces Q
Succinate-Q reductase - Answer An integral-membrane-protein complex of the inner
mitochondrial membrane that transfers electrons from FADH2FADH2 formed in the citric acid
cycle to coenzyme Q
Q-cytochrome c oxidoreductase - Answer A component of the respiratory chain, this
oxidoreductase carries electrons from coenzyme Q to cytochrome c and, in the process, pumps
protons out of the mitochondrial matrix to generate the proton-motive force.
Complex IV - Answer cytochrome c oxidase
Cytochrome C oxidase - Answer The final complex of the respiratory chain, it transfers
electrons from cytochrome c to molecular oxygen and concomitantly pumps protons across the
inner mitochondrial membrane to generate the proton-motive force
Cytochrome c - Answer Involved in energy transfer, it is a protein released from mitochondria
when cell is stressed.
Q cycle - Answer The shuttling of electrons between ubiquinol and ubiquinone in the inner
mitochondrial membrane as a part of Complex III's function
Respirasome - Answer moves electrons from ubiquinol (QH2) to oxygen
Superoxide dismutase - Answer catalyzes conversion of superoxide radicals to hydrogen
peroxide
Catalase - Answer An enzyme produced in all cells to decompose hydrogen peroxide, a by-
product of cell respiration
Complex V - Answer ATP synthase
ATP synthase - Answer Large protein that uses energy from H+ ions to bind ADP and a
phosphate group together to produce ATP
Proton-motive force - Answer The potential energy stored in the form of an electrochemical
gradient, generated by the pumping of hydrogen ions across biological membranes during
chemiosmosis.
