in mitochondrial electron transport, what is the direct role of o2?

in mitochondrial electron transport, what is the direct role of o2?


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Asked by 2 years ago
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Net Input: ADP, NAD, Glucose Net Output: ATP, NADH, Pyruvate In glycolysis, the six-carbon sugar glucose is converted to two molecules of pyruvate (three carbons each), with the net production of 2 ATP and 2 NADH per glucose molecule. There is no O2 uptake or CO2 release in glycolysis.Drag which molecules are involved in glycolysis
Net Input: NAD, coenzyme A, pyruvate Net Output: NADH, acetyl coenzyme A, CO In acetyl CoA formation, pyruvate (a product of glycolysis) is oxidized to acetyl CoA, with the reduction of NAD+ to NADH and the release of one molecule of CO2.
Net Input: Acetyl coenzyme A, NAD, ADP New Output: Coenzyme A, CO, NADH, ATP Not Input or Output: Pyruvate, Glucose, O In the citric acid cycle, the two carbons from the acetyl group of acetyl CoA are oxidized to two molecules of CO2, while several molecules of NAD+ are reduced to NADH and one molecule of FAD is reduced to FADH2. In addition, one molecule of ATP is produced.Citric Acid cycle
Net Input: NADH, ADP, O Net Output: NAD, ATP, CO, Water In oxidative phosphorylation, the NADH and FADH2 produced by the first three stages of cellular respiration are oxidized in the electron transport chain, reducing O2 to water and recycling NAD+ and FAD back to the first three stages of cellular respiration. The electron transport reactions supply the energy to drive most of a cell's ATP production.Oxidative Phosphorylation
Glycolysis - Cytosol, acetyl CoA - Mitochondrial matrix, citric acid cycle - Mitochondrial matrix, oxidative phosphorylation - inner mitochondrial membrane Cellular respiration begins with glycolysis in the cytosol. Pyruvate, the product of glycolysis, then enters the mitochondrial matrix, crossing both the outer and inner membranes. Both acetyl CoA formation and the citric acid cycle take place in the matrix. The NADH and FADH2 produced during the first three stages release their electrons to the electron transport chain of oxidative phosphorylation at the inner mitochondrial membrane. The inner membrane provides the barrier that creates an H+ gradient during electron transport, which is used for ATP synthesis.
1) Oxidized 2) Reduced 3) Glucose 4) Pyruvate 5) NAD 6) NADH
Among the products of glycolysis, which compounds contain energy that can be used by other biological reactions? O2 only pyruvate, ATP, and NADH ATP and NADH only pyruvate and ATP only CO2 only ATP only NADH onlyPyruvate, NADH, ATP ATP is the main product of cellular respiration that contains energy that can be used by other cellular processes. Some ATP is made in glycolysis. In addition, the NADH and pyruvate produced in glycolysis are used in subsequent steps of cellular respiration to make even more ATP.
Correct -One of the substrates is a molecule derived from the breakdown of glucose -An enzyme is required in order for the reaction to occur -A bond must be broken between an organic molecule and phosphate before ATP can formSort the statements into the appropriate bin depending on whether or not they correctly describe some aspect of substrate-level phosphorylation in glycolysis.
a. 2 b. 6 c. 6 d. 5 e. 4 f. 4 g. 4 h. 4 i. 4Identify the number of carbon atoms in each intermediate in acetyl CoA formation and the citric acid cycle. Labels may be used more than once.
a. CO b. NADH c. FAD d. FADH As in glycolysis, the electrons removed from carbon-containing intermediates during acetyl CoA formation and the citric acid cycle are passed to the electron carrier NAD+, reducing it to NADH. The citric acid cycle also uses a second electron carrier, FAD (flavin adenine dinucleotide), the oxidized form, and FADH2, the reduced form.show the net redox reaction in acetyl CoA formation and the citric acid cycle. Note that two types of electron carriers are involved.
Use your knowledge of the first three stages of cellular respiration to determine which explanation is correct. -More ATP is produced per CO2 released in cyclic processes than in linear processes. -It is easier to remove electrons and produce CO2 from compounds with three or more carbon atoms than from a two-carbon compound such as acetyl CoA. -Redox reactions that simultaneously produce CO2 and NADH occur only in cyclic processes. -Cyclic processes, such as the citric acid cycle, require a different mechanism of ATP synthesis than linear processes, such as glycolysis.It is easier to remove electrons and produce CO2 from compounds with three or more carbon atoms than from a two-carbon compound such as acetyl CoA. (Although it is possible to oxidize the two-carbon acetyl group of acetyl CoA to two molecules of CO2, it is much more difficult than adding the acetyl group to a four-carbon acid to form a six-carbon acid (citrate). Citrate can then be oxidized sequentially to release two molecules of CO2.)
In mitochondrial electron transport, what is the direct role of O2? -to oxidize NADH and FADH2 from glycolysis, acetyl CoA formation, and the citric acid cycle -to provide the driving force for the synthesis of ATP from ADP and Pi -to function as the final electron acceptor in the electron transport chain -to provide the driving force for the production of a proton gradientto function as the final electron acceptor in the electron transport chain (The only place that O2 participates in cellular respiration is at the end of the electron transport chain, as the final electron acceptor. Oxygen's high affinity for electrons ensures its success in this role. Its contributions to driving electron transport, forming a proton gradient, and synthesizing ATP are all indirect effects of its role as the terminal electron acceptor. )
How would anaerobic conditions (when no O2 is present) affect the rate of electron transport and ATP production during oxidative phosphorylation? (Note that you should not consider the effect on ATP synthesis in glycolysis or the citric acid cycle.) -Neither electron transport nor ATP synthesis would be affected. -Electron transport would stop but ATP synthesis would be unaffected. -Both electron transport and ATP synthesis would stop. -Electron transport would be unaffected but ATP synthesis would stop.Both electron transport and ATP synthesis would stop. (Oxygen plays an essential role in cellular respiration because it is the final electron acceptor for the entire process. Without O2, mitochondria are unable to oxidize the NADH and FADH2 produced in the first three steps of cellular respiration, and thus cannot make any ATP via oxidative phosphorylation. In addition, without O2 the mitochondria cannot oxidize the NADH and FADH2 back to NAD+ and FAD, which are needed as inputs to the first three stages of cellular respiration.)
Which statement best explains why more ATP is made per molecule of NADH than per molecule of FADH2? -FADH2 is made only in the citric acid cycle while NADH is made in glycolysis, acetyl CoA formation, and the citric acid cycle. -It takes more energy to make ATP from ADP and Pi using FADH2 than using NADH. -There is more NADH than FADH2 made for every glucose that enters cellular respiration. -Fewer protons are pumped across the inner mitochondrial membrane when FADH2 is the electron donor than when NADH is the electron donor. -The H+ gradient made from electron transport using NADH is located in a different part of the mitochondrion than the H+ gradient made using FADH2.ewer protons are pumped across the inner mitochondrial membrane when FADH2 is the electron donor than when NADH is the electron donor.
Remains the same: proton pumping rate, electron transport rate, rate of oxygen uptake Decreases or goes to zero: Rate of ATP synthesis, size of the proton gradient (Gramicidin causes membranes to become very leaky to protons, so that a proton gradient cannot be maintained and ATP synthesis stops. However, the leakiness of the membrane has no effect on the ability of electron transport to pump protons. Thus, the rates of proton pumping, electron transport, and oxygen uptake remain unchanged.)Sort the labels into the correct bin according to the effect that gramicidin would have on each process.
a. pyruvate b. NADH c. NAD d. NADH e. NAD
Under anaerobic conditions (a lack of oxygen), the conversion of pyruvate to acetyl CoA stops. Which of these statements is the correct explanation for this observation? -ATP is needed to convert pyruvate to acetyl CoA. Without oxygen, no ATP can be made in oxidative phosphorylation. -Oxygen is an input to acetyl CoA formation. -Oxygen is required to convert glucose to pyruvate in glycolysis. Without oxygen, no pyruvate can be made. -In the absence of oxygen, electron transport stops. NADH is no longer converted to NAD+, which is needed for the first three stages of cellular respiration.In the absence of oxygen, electron transport stops. NADH is no longer converted to NAD+, which is needed for the first three stages of cellular respiration. (NAD+ couples oxidative phosphorylation to acetyl CoA formation. The NAD+ needed to oxidize pyruvate to acetyl CoA is produced during electron transport. Without O2, electron transport stops, and the oxidation of pyruvate to acetyl CoA also stops because of the lack of NAD+. )
ATP levels would fall at first, decreasing the inhibition of PFK and increasing the rate of ATP production.
Glucose utilization would increase a lot. (ATP made during fermentation comes from glycolysis, which produces a net of only 2 ATP per glucose molecule. In contrast, aerobic cellular respiration produces about 36 ATP per glucose molecule. To meet the same ATP demand under anaerobic conditions as under aerobic conditions, a cell's rate of glycolysis and glucose utilization must increase nearly 20-fold.)
in mitochondrial
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