Electron Transport Chain (Respiratory Chain) - exercise - Vladimíra Kvasnicová

Transcription

1 Electron Transport Chain (Respiratory Chain) - exercise - Vladimíra Kvasnicová

2 Respiratory chain (RCH) a) is found in all cells b) is located in a mitochondrion c) includes enzymes integrated in the inner mitochondrial membrane d) produces reducing equivalents (NADH+H +, FADH 2 )

3 Respiratory chain (RCH) a) is found in all cells b) is located in a mitochondrion c) includes enzymes integrated in the inner mitochondrial membrane d) produces reducing equivalents (NADH+H +, FADH 2 )

4 The figure is found at (December 2006)

5 Respiratory chain (RCH) a) belongs among oxidative pathways b) can proceed under both aerobic and anaerobic conditions c) is a reversible pathway d) needs oxygen (O 2 ) for its function

6 Respiratory chain (RCH) a) belongs among oxidative pathways b) can proceed under both aerobic and anaerobic conditions c) is a reversible pathway d) needs oxygen (O 2 ) for its function

7 reducing properties Gibbs energy G Redox potential E oxidizing properties The figure is found at Ed1/Chapter14_13/REDOX_POTENTIALS_ElectronTransportChain_Fig14-21.htm (December 2006)

8 The figure is found at (December 2006)

9 Enzymes of the RCH a) belongs among oxidoreductases b) can transfer either H or electrons c) are called Complex I, II, III and IV d) transfer protons and electrons in the same direction

10 Enzymes of the RCH a) belongs among oxidoreductases b) can transfer either H or electrons c) are called Complex I, II, III and IV d) transfer protones and electrones in the same direction

11 proton = H + electron = e - Cytochrome c is drawn wrongly! It is found in the intermembrane space, bound to the inner mitochondrial membrane The figure is adopted from the book: Devlin, T. M. (editor): Textbook of Biochemistry with Clinical Correlations, 4th ed. Wiley-Liss, Inc., New York, ISBN

12 The function of the RCH a) is to regenerate NAD + from NADH b) is to regenerate NADP + from NADPH c) is to regenerate FAD from FADH 2 d) is to finish oxidation of energy substrates and conserve their energy in a form of ATP

13 The function of the RCH a) is to regenerate NAD + from NADH b) is to regenerate NADP + from NADPH c) is to regenerate FAD from FADH 2 d) is to finish oxidation of energy substrates and conserve their energy in a form of ATP

14 In reactions of the RCH a) oxygen is reduced to H 2 O b) protons (H + ) are transfered into an intermembrane space c) ATP is produced by the Complex I d) all reduced coenzymes (NADH+H + and FADH 2 ) are reoxidized by the same mechanism

15 In reactions of the RCH a) oxygen is reduced to H 2 O b) protons (H + ) are transfered into an intermembrane space c) ATP is produced by the Complex I d) all reduced coenzymes (NADH+H+ and FADH 2 ) are reoxidized by the same mechanism

16 The figure is found at (December 2006)

17 Choose correct statement a) Complex I transfers H + into an intermembrane space b) Complex II transfers H + into an intermembrane space c) Coenzyme Q accepts e- from both Complex I and Complex II d) Complex IV transfers electrones to oxygen

18 Choose correct statement a) Complex I transfers H + into an intermembrane space b) Complex II transfers H + into an intermembrane space c) Coenzyme Q accepts e- from both Complex I and Complex II d) Complex IV transfers electrones to oxygen

19 proton = H + electron = e - Cytochrome c is drawn wrongly! It is found in the intermembrane space, bound to the inner mitochondrial membrane The figure is adopted from the book: Devlin, T. M. (editor): Textbook of Biochemistry with Clinical Correlations, 4th ed. Wiley-Liss, Inc., New York, ISBN

20 Citrate cycle (CC) and the RCH are interconnected a) by CO 2 (produced by CC, used by RCH) b) by NADH (produced by CC, used by RCH) c) an enzyme succinate dehydrogenase d) ATP (produced by RCH, used by CC)

21 Citrate cycle (CC) and the RCH are interconnected a) by CO 2 (produced by CC, used by RCH) b) by NADH (produced by CC, used by RCH) c) an enzyme succinate dehydrogenase d) ATP (produced by RCH, used by CC)

22 Citrate cycle succinate DH The figure is found at (December 2006)

23 Adenosine triphosphate (ATP) a) can be produced only in a cooperation with the RCH b) can be synthesized only under aerobic conditions c) is formed from ADP by addition of one phosphate d) is transported from a mitochondrion into a cytoplasm by exchange with ADP

24 Adenosine triphosphate (ATP) a) can be produced only in a cooperation with the RCH b) can be synthesized only under aerobic conditions c) is formed from ADP by addition of one phosphate d) is transported from a mitochondrion into a cytoplasm by exchange with ADP

25 ATP-ADP translocase The figure is adopted from the book: Devlin, T. M. (editor): Textbook of Biochemistry with Clinical Correlations, 4th ed. Wiley-Liss, Inc., New York, ISBN

26 When the term is used it always means ATP synthesis a) phosphorylation b) oxidative phosphorylation c) aerobic phosphorylation d) substrate level phosphorylation

27 When the term is used it always means ATP synthesis a) phosphorylation b) oxidative phosphorylation c) aerobic phosphorylation d) substrate level phosphorylation

28 Oxidative phosphorylation a) needs proton gradient on the inner mitochondrial membrane b) is catalyzed by ATP synthase c) can be interrupted by uncoupling proteins (UCP) d) means ATP synthesis in any oxidative metabolic pathway

29 Oxidative phosphorylation a) needs proton gradient on the inner mitochondrial membrane b) is catalyzed by ATP synthase c) can be interrupted by uncoupling proteins (UCP) d) means ATP synthesis in any oxidative metabolic pathway

30 The figure is adopted from the book: Devlin, T. M. (editor): Textbook of Biochemistry with Clinical Correlations, 4th ed. Wiley-Liss, Inc., New York, ISBN

31 inner mitochondrial membrane ATP synthase The figure is found at (December 2006)

32 Uncoupling proteins (UCP) = separate RCH from ATP synthesis (the synthesis is interrupted) energy from H + gradient is released as a heat The figure is found at (December 2006)

33 ATP can be formed by the reactions a) glucose-6-p + ADP glucose + ATP b) succinyl~coa + GDP succinate + GTP c) GTP + ADP GDP + ATP d) ADP + ADP ATP + AMP

34 ATP can be formed by the reactions a) glucose-6-p + ADP glucose + ATP b) succinyl~coa + GDP succinate + GTP c) GTP + ADP GDP + ATP d) ADP + ADP ATP + AMP (adenylate kinase = myokinase)

35 Oxidation of NADH+H + in the RCH produces more ATP than oxidation of FADH 2 because a) higher proton gradien is made by oxidation of NADH+H + b) NADH+H + transfers H to different Complex of the RCH than FADH 2 c) more protons are transported to the intermembrane space if NADH+H + is oxidized d) more e - are transfered from NADH+H + to O 2

36 Oxidation of NADH+H + in the RCH produces more ATP than oxidation of FADH 2 because a) higher proton gradien is made by oxidation of NADH+H + b) NADH+H + transfers H to different Complex of the RCH than FADH 2 c) more protons are transported to the intermembrane space if NADH+H + is oxidized d) more e - are transfered from NADH+H + to O 2

37 FADH 2 The figure is found at (December 2006)

38 Choose correct statement(s) about regulation of RCH and ATP synthesis a) O 2 decreases the pathways b) uncoupling proteins increases ATP synthesis c) ADP increses ATP synthesis d) NADH+H + /NAD + increases the pathways

39 Choose correct statement(s) about regulation of RCH and ATP synthesis a) O 2 decreases the pathways b) uncoupling proteins increases ATP synthesis c) ADP increses ATP synthesis d) NADH+H + /NAD + increases the pathways