Podcast
Questions and Answers
What is the primary function of complex IV in the electron transport chain?
What is the primary function of complex IV in the electron transport chain?
How many protons are pumped across the inner mitochondrial membrane by complex III for every two electrons transferred?
How many protons are pumped across the inner mitochondrial membrane by complex III for every two electrons transferred?
Which compound serves as the final electron acceptor in the electron transport chain?
Which compound serves as the final electron acceptor in the electron transport chain?
What is a common inhibitor of complex II in the electron transport chain?
What is a common inhibitor of complex II in the electron transport chain?
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Which process is directly driven by the energy released during electron transfer in the electron transport chain?
Which process is directly driven by the energy released during electron transfer in the electron transport chain?
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How many electrons are required to fully reduce one molecule of oxygen at complex IV?
How many electrons are required to fully reduce one molecule of oxygen at complex IV?
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Which of the following inhibitors affects the transfer of electrons from cytochrome b to Coenzyme Q?
Which of the following inhibitors affects the transfer of electrons from cytochrome b to Coenzyme Q?
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What is the primary role of oxidative phosphorylation?
What is the primary role of oxidative phosphorylation?
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What is the outcome of the electron transfer process when electrons are shuttled to complex IV?
What is the outcome of the electron transfer process when electrons are shuttled to complex IV?
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What catalyzes the synthesis of ATP during chemiosmosis?
What catalyzes the synthesis of ATP during chemiosmosis?
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During oxidative phosphorylation, where do electrons travel after being donated by NADH and FADH₂?
During oxidative phosphorylation, where do electrons travel after being donated by NADH and FADH₂?
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What happens to protons as they are pumped across the inner mitochondrial membrane?
What happens to protons as they are pumped across the inner mitochondrial membrane?
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What is a consequence of the final electron acceptance in oxidative phosphorylation?
What is a consequence of the final electron acceptance in oxidative phosphorylation?
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What is formed as a result of the proton gradient during chemiosmosis?
What is formed as a result of the proton gradient during chemiosmosis?
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What role does oxidative phosphorylation play in cellular respiration?
What role does oxidative phosphorylation play in cellular respiration?
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What does ATP levels influence in terms of cellular processes?
What does ATP levels influence in terms of cellular processes?
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What is the primary function of the inner mitochondrial membrane?
What is the primary function of the inner mitochondrial membrane?
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Which cofactors are involved in the catalytic activity of pyruvate dehydrogenase?
Which cofactors are involved in the catalytic activity of pyruvate dehydrogenase?
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Which statement best describes the overall products resulting from one cycle of the TCA cycle per acetyl-CoA?
Which statement best describes the overall products resulting from one cycle of the TCA cycle per acetyl-CoA?
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Which component is NOT part of the electron transport chain (ETC) in mitochondria?
Which component is NOT part of the electron transport chain (ETC) in mitochondria?
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How does oxidative phosphorylation primarily generate ATP?
How does oxidative phosphorylation primarily generate ATP?
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What role does the intermembrane space play in cellular respiration?
What role does the intermembrane space play in cellular respiration?
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Which protein complex in the electron transport chain directly transfers electrons to oxygen?
Which protein complex in the electron transport chain directly transfers electrons to oxygen?
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What process is responsible for creating a proton gradient across the inner mitochondrial membrane?
What process is responsible for creating a proton gradient across the inner mitochondrial membrane?
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What is primarily created by the movement of H+ ions during chemiosmosis?
What is primarily created by the movement of H+ ions during chemiosmosis?
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Which component of ATP synthase is primarily responsible for forming a channel for protons?
Which component of ATP synthase is primarily responsible for forming a channel for protons?
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How is the proton motive force established in the inner mitochondrial membrane?
How is the proton motive force established in the inner mitochondrial membrane?
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During oxidative phosphorylation, what roles does chemiosmosis serve?
During oxidative phosphorylation, what roles does chemiosmosis serve?
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What drives the flow of protons through the ATP synthase during ATP production?
What drives the flow of protons through the ATP synthase during ATP production?
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What primarily constitutes the components of proton motive force?
What primarily constitutes the components of proton motive force?
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Which of the following accurately describes the function of the F1 component of ATP synthase?
Which of the following accurately describes the function of the F1 component of ATP synthase?
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Which complex in the electron transport chain is NOT involved in the active transport of protons?
Which complex in the electron transport chain is NOT involved in the active transport of protons?
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Which of the following best describes the primary function of uncoupling proteins (UCPs)?
Which of the following best describes the primary function of uncoupling proteins (UCPs)?
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What is the primary effect of proton leakage caused by uncouplers in oxidative phosphorylation?
What is the primary effect of proton leakage caused by uncouplers in oxidative phosphorylation?
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Which uncoupling protein is primarily associated with heat generation?
Which uncoupling protein is primarily associated with heat generation?
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In the context of mitochondrial function, what is the effect of increased oxygen consumption when uncouplers are present?
In the context of mitochondrial function, what is the effect of increased oxygen consumption when uncouplers are present?
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What condition can result from defects in the electron transport chain (ETC)?
What condition can result from defects in the electron transport chain (ETC)?
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Which of the following is NOT a characteristic of uncoupler action in the mitochondrial membrane?
Which of the following is NOT a characteristic of uncoupler action in the mitochondrial membrane?
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Which chemical is known for its effect as a potent uncoupler of oxidative phosphorylation?
Which chemical is known for its effect as a potent uncoupler of oxidative phosphorylation?
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Which uncoupling protein is associated with various tissues, including the brain and pancreas?
Which uncoupling protein is associated with various tissues, including the brain and pancreas?
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What is the immediate consequence of uncoupling oxidative phosphorylation?
What is the immediate consequence of uncoupling oxidative phosphorylation?
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Which of the following effects is associated with the action of uncouplers?
Which of the following effects is associated with the action of uncouplers?
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ATP synthesis is catalyzed by the enzyme ______.
ATP synthesis is catalyzed by the enzyme ______.
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NADH and FADH₂ donate electrons to the electron transport chain during ______.
NADH and FADH₂ donate electrons to the electron transport chain during ______.
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The pumping of protons creates a proton gradient across the inner mitochondrial ______.
The pumping of protons creates a proton gradient across the inner mitochondrial ______.
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Electrons are transferred to molecular oxygen (O₂) at Complex ______, forming water as a byproduct.
Electrons are transferred to molecular oxygen (O₂) at Complex ______, forming water as a byproduct.
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The primary role of oxidative phosphorylation is to generate approximately ______ ATP molecules per glucose molecule.
The primary role of oxidative phosphorylation is to generate approximately ______ ATP molecules per glucose molecule.
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During ATP synthesis via chemiosmosis, protons flow back into the matrix through ______.
During ATP synthesis via chemiosmosis, protons flow back into the matrix through ______.
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Chemiosmosis establishes a ______ potential, driving ATP synthesis.
Chemiosmosis establishes a ______ potential, driving ATP synthesis.
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Energy from reduced cofactors (NADH and FADH₂) is converted into chemical energy stored in ______.
Energy from reduced cofactors (NADH and FADH₂) is converted into chemical energy stored in ______.
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Chemiosmosis involves the movement of ions across a ______ membrane bound structure.
Chemiosmosis involves the movement of ions across a ______ membrane bound structure.
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In eukaryotes, chemiosmosis occurs in the inner ______ membrane.
In eukaryotes, chemiosmosis occurs in the inner ______ membrane.
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The proton motive force refers to the electrochemical gradient of ______ across a biological membrane.
The proton motive force refers to the electrochemical gradient of ______ across a biological membrane.
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ATP synthase is responsible for ATP production using energy from the proton ______ force.
ATP synthase is responsible for ATP production using energy from the proton ______ force.
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The F₀ component of ATP synthase forms a ______ for protons to flow back into the mitochondrial matrix.
The F₀ component of ATP synthase forms a ______ for protons to flow back into the mitochondrial matrix.
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The process of creating a proton gradient begins with the transfer of ______ through the electron transport chain.
The process of creating a proton gradient begins with the transfer of ______ through the electron transport chain.
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The protons flow back into the matrix through ATP synthase driven by ______ and electrochemical potential.
The protons flow back into the matrix through ATP synthase driven by ______ and electrochemical potential.
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The active transport of protons occurs at complexes I, III, and ______ in the electron transport chain.
The active transport of protons occurs at complexes I, III, and ______ in the electron transport chain.
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Complex IV receives electrons from cytochrome c and transfers them to ______
Complex IV receives electrons from cytochrome c and transfers them to ______
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The transfer of electrons to oxygen leads to the formation of ______
The transfer of electrons to oxygen leads to the formation of ______
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NADH and FADH₂ donate electrons to ______ in the electron transport chain.
NADH and FADH₂ donate electrons to ______ in the electron transport chain.
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Complex I pumps ______ protons across the inner mitochondrial membrane.
Complex I pumps ______ protons across the inner mitochondrial membrane.
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Antimycin inhibits the transfer of electrons from cytochrome ______ to Coenzyme Q.
Antimycin inhibits the transfer of electrons from cytochrome ______ to Coenzyme Q.
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The final electron acceptor, oxygen, requires ______ electrons to reduce one O₂ molecule.
The final electron acceptor, oxygen, requires ______ electrons to reduce one O₂ molecule.
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Cyanide and azide are inhibitors of ______ in the electron transport chain.
Cyanide and azide are inhibitors of ______ in the electron transport chain.
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The electron transfer process drives the pumping of protons across the ______ mitochondrial membrane.
The electron transfer process drives the pumping of protons across the ______ mitochondrial membrane.
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The influx of protons causes the c-ring in the F₀ component to ______
The influx of protons causes the c-ring in the F₀ component to ______
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The rotational energy induces conformational changes in the F₁ component, facilitating the binding of ______ and inorganic phosphate (Pi)
The rotational energy induces conformational changes in the F₁ component, facilitating the binding of ______ and inorganic phosphate (Pi)
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The P/O ratio measures the efficiency of oxidative phosphorylation in the electron transport chain and ATP synthesis in ______
The P/O ratio measures the efficiency of oxidative phosphorylation in the electron transport chain and ATP synthesis in ______
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Each NADH donates two electrons to the ETC, resulting in about ______ ATP per oxygen atom
Each NADH donates two electrons to the ETC, resulting in about ______ ATP per oxygen atom
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From one molecule of glucose, the total reaction yields about ______ ATPs.
From one molecule of glucose, the total reaction yields about ______ ATPs.
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During glycolysis, substrate-level phosphorylation produces ______ ATP.
During glycolysis, substrate-level phosphorylation produces ______ ATP.
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During the TCA cycle, ______ NADH yields 15 ATP.
During the TCA cycle, ______ NADH yields 15 ATP.
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NADH produced in the cytoplasm during glycolysis must be transported into the mitochondria using the ______ shuttle systems.
NADH produced in the cytoplasm during glycolysis must be transported into the mitochondria using the ______ shuttle systems.
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In eukaryotes, ETC takes place in the inner membrane of ______.
In eukaryotes, ETC takes place in the inner membrane of ______.
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ETC serves as electron carriers in the final stage of cellular ______.
ETC serves as electron carriers in the final stage of cellular ______.
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Complex I is also known as ______ dehydrogenase.
Complex I is also known as ______ dehydrogenase.
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Complex II is known as succinate-coenzyme Q ______.
Complex II is known as succinate-coenzyme Q ______.
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The proton gradient created during the electron transport chain is used to drive ______ formation.
The proton gradient created during the electron transport chain is used to drive ______ formation.
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Complex III is also known as cytochrome ______ complex.
Complex III is also known as cytochrome ______ complex.
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Complex IV catalyzes the transfer of electrons from cytochrome c to molecular ______.
Complex IV catalyzes the transfer of electrons from cytochrome c to molecular ______.
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During the Q cycle in Complex III, one of the outcomes is the release of two ______ into the intermembrane space.
During the Q cycle in Complex III, one of the outcomes is the release of two ______ into the intermembrane space.
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Electrons from FADH2 enter the electron transport chain through ______.
Electrons from FADH2 enter the electron transport chain through ______.
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Complex I transfers electrons to ______, converting it into CoQH2.
Complex I transfers electrons to ______, converting it into CoQH2.
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Complex II has a parallel electron transport pathway to Complex ______.
Complex II has a parallel electron transport pathway to Complex ______.
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Cytochrome ______ is reduced during the electron transfer from Complex III.
Cytochrome ______ is reduced during the electron transfer from Complex III.
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The composition of Complex IV includes cytochrome a, cytochrome a3, and two ______ centers.
The composition of Complex IV includes cytochrome a, cytochrome a3, and two ______ centers.
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NADH collects the pair of electrons from ______ and passes them to ubiquinone.
NADH collects the pair of electrons from ______ and passes them to ubiquinone.
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Study Notes
Introduction to Oxidative Phosphorylation
- Process of ATP production using the energy from the electron transport chain and proton gradient.
- Involves oxidation and phosphorylation events.
- Occurs in the inner mitochondrial membrane.
Electron Transport Chain
- Series of protein complexes embedded in the inner mitochondrial membrane.
- Transfers electrons from electron carriers (NADH and FADH₂) to oxygen.
- Energy released from electron transfer is used to pump protons (H⁺) from the mitochondrial matrix into the intermembrane space, creating a proton gradient.
- Four main protein complexes : I, II, III, IV.
- Mobile carriers : Coenzyme Q (ubiquinone) and cytochrome c.
- Complex I : Pumps 4 protons (H⁺).
- Complex III: Pumps 4 protons (H⁺).
- Complex IV: Pumps 2 protons (H⁺).
Chemiosmosis
- Movement of ions across a semipermeable membrane down the electrochemical gradient.
- Proton gradient established by the ETC drives ATP synthesis via ATP synthase.
Proton Motive Force (PMF)
- Electrochemical gradient of protons (H⁺ ions) across a biological membrane.
- Components: difference in H⁺ concentration and difference in charge.
- Drives ATP synthesis.
ATP Synthase
- Multi-subunit enzyme complex responsible for ATP production using the energy from the proton motive force.
- F₀ component: Embedded in the inner mitochondrial membrane, forms a channel for protons to flow back into the matrix.
- F₁ component: Projects into the mitochondrial matrix, catalyzes the conversion of ADP and inorganic phosphate into ATP.
Mechanism of ATP Synthesis
- Protons flow back into the matrix through the F₀ component of ATP synthase, driven by the gradient and electrochemical potential.
- This flow drives the production of ATP by the F₁ component.
Uncouplers of Oxidative Phosphorylation
- Substances that disrupt the coupling between the ETC and ATP synthesis.
- Cause protons to flow back into the mitochondrial matrix independently of ATP synthase.
- Examples: 2,4-Dinitrophenol (DNP) and Carbonyl Cyanide m-Chlorophenyl Hydrazone (CCCP).
- Uncoupling proteins (UCPs) are regulated proton channels or transporters found in the inner mitochondrial membrane.
- They play important roles in energy metabolism and thermogenesis.
Uncoupling Proteins
- Function: Modulate energy metabolism, insulin secretion, reduce oxidative stress, and protect against oxidative damage.
- Location: Brown Adipose Tissue (BAT), brain, skeletal muscle, and pancreas.
Oxidative Phosphorylation Disorder
- Genetic or acquired defects in the ETC impair ATP production.
- Caused by mutations in mitochondrial DNA or nuclear DNA affecting ETC complexes.
Electron Transport Chain Inhibitors
- Inhibitors that stop the transfer of electrons in the ETC, leading to decreased ATP production.
- Examples: Rotenone, Amytal, Halothanes, Carbon monoxide (CO), cyanide (CN-), and azide (N3-).
Oxidative Phosphorylation
-
Process of Oxidative Phosphorylation:
- Electron Donation: NADH and FADH₂ generated from glycolysis and the TCA cycle donate electrons to the electron transport chain (ETC).
- Electron Transport: Electrons travel through four protein complexes (I-IV) embedded in the inner mitochondrial membrane.
- Proton Gradient Creation: The pumping of protons creates a proton gradient across the inner mitochondrial membrane, establishing a chemiosmotic potential (proton motive force).
- ATP Synthesis via Chemiosmosis: Protons flow back into the matrix through ATP synthase. The flow drives the production of ATP.
- Final Electron Acceptance: Electrons are transferred to molecular oxygen (O₂) at Complex IV, forming water (H₂O) as a byproduct.
Function of Oxidative Phosphorylation
- ATP Production: Primary role is to generate approximately 26-28 ATP molecules per glucose molecule, providing energy for cellular processes.
- Energy Conversion: Converts energy from reduced cofactors (NADH and FADH₂) into chemical energy stored in ATP.
- Cellular Respiration Integration: Completes the process of cellular respiration by utilizing oxygen as the final electron acceptor, producing water.
- Metabolic Regulation: Regulates key metabolic pathways by responding to changes in cellular energy demands; ATP levels influence various biochemical reactions.
- Heat Generation: Some energy is dissipated as heat, aiding in thermoregulation and maintaining body temperature in humans.
Electron Transport Chain (ETC)
- Overview: A series of proteins that transfer electrons through a membrane within mitochondria to form a gradient of protons that drives the creation of ATP.
- Location: In eukaryotes, ETC takes place in the inner membrane of mitochondria. Protons are transported from the matrix to the intermembrane space across the inner mitochondrial membrane.
- Role in Cellular Respiration: ETC serves as electron carriers in the final stage of cellular respiration. ETC generates proton gradients for chemiosmosis (ATP synthesis).
Components of the ETC
-
Complex I (NADH dehydrogenase):
- also known as NADH: ubiquinone oxidoreductase; accepts electrons from NADH and passes them to ubiquinone (Coenzyme Q).
- Composition: NADH dehydrogenase, flavin mononucleotide (FMN), iron-sulfur clusters (Fe-S)
- Reaction: NADH + H+ + CoQ + 4H+in→ NAD+ + CoQH2 + 4H+out
-
Complex II (Succinate dehydrogenase):
- Also known as succinate-coenzyme Q reductase; the only enzyme that participates in both the citric acid cycle and the electron transport chain.
- Composition: succinate dehydrogenase (SDHA); succinate dehydrogenase [ubiquinone] iron-sulfur (Fe-S) subunit mitochondrial (SDHB); succinate dehydrogenase complex subunit C (SDHC); and succinate dehydrogenase complex subunit D (SDHD)
- Function: Catalyzes the transfer of electrons from other donors like fatty acids and glycerol-3 phosphate to coenzyme Q.
- Reaction: Succinate + FADH2 + CoQ → Fumarate + FAD+ + CoQH2
-
Complex III (Coenzyme Q: cytochrome c – oxidoreductase):
- Also known as cytochrome bc1 complex.
- Composition: cytochrome b, cytochrome c and a specific Fe-S center.
- Catalyzes the transfer of electrons from the reduced coenzyme Q to cytochrome c for transport to Complex IV.
- Uses energy released to pump more protons across the inner mitochondrial membrane.
- Reaction: CoQH2 + 2 cytochrome c (Fe3+) → CoQ + 2 cytochrome c (Fe2+) + 4H+
-
Complex IV (Cytochrome c Oxidase):
- Last enzyme in ETC.
- Composition: cytochrome a, cytochrome a3, and two copper centers, the CuA and CuB centers.
- Catalyzes the transfer of two electrons from cytochrome c to molecular oxygen (O2), reducing it to water.
- Electrons travel from the intermembrane space side to the mitochondrial matrix side, against the charge gradient.
- Reaction: 4 cytc c (Fe 2+) + O2+ 4H+ → 4 cytc c (Fe3+) + 2H2O
Electron Transport Chain Steps
- Transfer of electrons from NADH to Coenzyme Q: NADH, produced during glycolysis and the citric acid cycle, donates electrons to complex I. Complex I transfers the electrons to Coenzyme Q while pumping protons across the inner mitochondrial membrane, creating a proton gradient.
- Transfer of electrons from FADH2 to Coenzyme Q: The oxidation of succinate to fumarate results in the reduction of FAD to FADH2. The electrons from FADH2 enter the electron transport chain catalyzed by complex II. Complex II doesn’t pump any protons across the membrane.
- Transfer of electrons from CoQH2 to cytochrome c: Complex III receives electrons from Coenzyme Q and transfers them to cytochrome c. As electrons are transferred in complex III, protons are pumped across the inner mitochondrial membrane. Cytochrome c accepts electrons from complex III and shuttles them to complex IV.
- Transfer of electrons from cytochrome c to molecular oxygen: Complex IV receives electrons from cytochrome c and transfers them to molecular oxygen (O2). The transfer of electrons to oxygen leads to the formation of water (H2O). Complex IV also pumps protons across the inner mitochondrial membrane.
Summary of Electron Transport Chain
-
Electron Transfer: NADH and FADH₂ donate electrons:
- NADH → Complex I (two electrons transfer)
- FADH₂ → Complex II (two electrons transfer)
-
Proton Pumps: Energy from electron transfer drives proton pumping:
- Complex I: Pumps 4 protons (H⁺)
- Complex III: Pumps 4 protons (H⁺)
- Complex IV: Pumps 2 protons (H⁺)
-
Role of Oxygen: Final Electron Acceptor:
- Oxygen is reduced at Complex IV.
- Accepts 2 electrons and combines with protons to form water (H₂O).
- Requires 4 electrons to reduce 1 O₂ molecule.
Electron Transport Chain Inhibitors
-
Complex I inhibitors:
- Rotenone: Inhibits the reduction of Coenzyme Q.
- Amytal and Halothanes: Inhibits the transfer of electrons from the Fe-S centers to Coenzyme Q.
-
Complex II inhibitors:
- Competitive inhibitors with the substrate succinate.
- Examples: carboxin, thenoyltrifluoroacetone and malonate.
-
Complex III inhibitors: (antibiotics)
- Antimycin: Inhibits the transfer of electrons from cytochrome b to Coenzyme Q.
- Myxothiazol and stigmatellin: Inhibits the transfer of electrons from reduced form of Coenzyme Q to cytochrome c.
-
Complex IV inhibitors:
- Cyanide (CN-) and azide (N3-): block the transfer of electrons from cytochrome a to CuA center.
- Carbon monoxide (CO): binds to the reduced form of cytochrome a3, and prevents electron transfer to O2.
Chemiosmosis
-
Definition: The movement of ions across a semipermeable membrane bound structure, down their electrochemical gradient.
- This process is important in the formation of ATP by the movement of H+ across a membrane during cellular respiration.
- Location: In eukaryotes, chemiosmosis occurs in the inner mitochondrial membrane. Protons are pumped into the intermembrane space, creating a proton gradient that drives ATP synthesis via ATP synthase.
-
Role in Cellular Respiration: Chemiosmosis plays a crucial role in oxidative phosphorylation by enabling ATP production.
- It assists in establishing a proton gradient, converting energy, regulating metabolism, maintaining membrane potential, and facilitating transport processes.
Proton Motive Force (PMF)
- Definition: The electrochemical gradient of protons (H⁺ ions) across a biological membrane, primarily the inner mitochondrial membrane in eukaryotes.
- Components: Difference in H⁺ concentration (more H⁺ outside than inside). Difference in charge (more positive outside due to H⁺ accumulation).
- Formation: Active transport of protons by complexes I, III, and IV in the ETC.
- Function: Drives ATP synthesis via ATP synthase.
ATP Synthase
- Definition: A multi-subunit enzyme complex responsible for ATP production using the energy from the proton motive force.
-
Structure:
- F₀ Component: Embedded in the inner mitochondrial membrane. Forms a channel for protons (H⁺) to flow back into the matrix, driven by proton motive force. Composed of a ring of c-subunits that rotate upon proton passage
- F₁ Component: Projects into the mitochondrial matrix. Catalyzes the conversion of ADP and inorganic phosphate (Pi) into ATP. Contains three α and three β subunits that form the catalytic sites.
Mechanism of ATP Synthesis
- Proton Gradient Formation: Electrons are transferred through the electron transport chain (ETC). Protons (H⁺) are pumped from the mitochondrial matrix to the intermembrane space, creating a proton gradient.
- Proton Flow through ATP Synthase: Protons flow back into the matrix through the F₀ component of ATP synthase. This flow is driven by the gradient and electrochemical potential.
- Rotation of F₀: The influx of protons causes the c-ring in the F₀ component to rotate. This mechanical energy is transmitted to the F₁ component.
- ATP Formation: The rotational energy induces conformational changes in the F₁ component, facilitating the binding of ADP and inorganic phosphate (Pi). This leads to the synthesis of ATP from ADP and Pi.
P/O Ratio and ATP Production
-
Definition: The P/O ratio (phosphate to oxygen ratio) is a measure of the efficiency of oxidative phosphorylation in the electron transport chain (ETC) and ATP synthesis in mitochondria.
- The P/O ratio indicates the number of ATP molecules produced during the transfer of two electrons in the ETC, terminated by reduction of one oxygen atom.
-
Typical P/O Ratio:
- From NADH: Each NADH donates two electrons to the ETC, 10 protons (H+) pumped. Typically yielding about 2.5 to 3 ATP per oxygen atom.
- From FADH2: Each FADH₂ donates two electrons to the ETC, 6 protons (H+) pumped. Typically yields about 1.5 to 2 ATP per oxygen atom.
ATP Yield
-
Total Electron Carriers: C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + 30-32 ATP
- 10 NADH
- 2 FADH₂
- Assuming 2.5 ATP per NADH, 1.5 ATP per FADH2
-
ATP Yield:
- Glycolysis: 2 ATP from substrate-level phosphorylation. 2 NADH yields 3 ATP or 5 ATP.
- Pyruvate Oxidation (Two Pyruvates): 2 NADH yields 5 ATP.
-
TCA Cycle (Two Acetyl-CoA):
- 6 NADH yields 15 ATP
- 2 FADH₂ yields 3 ATP
- 2 ATP from substrate-level phosphorylation
- Total: 30 or 32 ATP
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Description
This quiz explores the key concepts of oxidative phosphorylation, including the electron transport chain and chemiosmosis. Understand how ATP is produced through the energy generated from electron transfers and proton gradients within the mitochondria. Test your knowledge of the main protein complexes involved in this vital biochemical process.
