Ch 19 Clicker Questions

2. How many electrons would enter Complex I from complete oxidation of myristic acid 14:0? a. 18 b. 52 c. 42 d. 54 e. 40

D. 54

1. Which enzyme would NOT be expected to contribute electron carriers to oxidative phophorylation? a. alcohol dehydrogenase b. malate dehydrogenase c. succinate dehydrogenase d. glucose 6-phosphate dehydrogenase e. glyceraldehyde 3-phosphate dehydrogenase

D. glucose 6-phosphate dehydrogenase

6. Which molecule is part of an important mass action in most cells and is a modulator of the three major ATP-producing pathways? a. ADP b. NAD+ c. AMP d. acetate e. NADH

a. ADP

13. The electron transport chain generates ATP by: a. creating a proton-motive force b. substrate-level phosphorylation c. activating uncoupling protein 1 (UCP1) d. pumping phosphate ions into the intermembrane space e. adding electrons to ADP to form ATP

a. creating a proton-motvie force

11. What is the soluble electron carrier in chloroplast photosystems, a molecule analogous to cytochrome c in mitochondria? a. plastocyanin b. cytochrome c2 c. cytochrome bc1 complex d. rhodopsin e. transfer of a H+ across a membrane

a. plastocyanin

4. Which electron carrier or prosthetic group would not function after site-directed mutagenesis substituted Pro for Cys in succinate dehydrogenase? a. cytochrome c b. iron-sulfur center c. flavin adenine dinucleotide d. ibiquinone e. FMN

b. iron-sulfur center

14. Why are reactive oxygen species (ROS) generated? a. molecular oxygen recombines with hydrogen to produce dihydrogen oxide b. stray electrons bind to oxygen creating a free radical oxygen species c. there are high ADP levels d. there is a high NAD+/NADH ration e. transfer of H+ across the inner mitochondrial membrane is uncoupled from ATP synthase

b. stray electrons bind to oxygen creatinf a free radical oxygen species

3. A mutation in soy plants renders ferridoxin-NADP+ oxidoreductase nonfuntional. What can take its place, functionally? a. the Calvin cycle b. the Krebs cycle c. the Pentose Phosphate Pathway d. the Glyoxylate cyle e. Lactate dehydrogenase

c. the Pentose Phosphate Pathways

17. Why is the glycerol-3-phosphate shuttle necessary for oxidative phosphorylation in the brain? a. to bring dihydroxyacetone phosphate into the mitochondrial matrix b. to bring glycerol-3-phosphate out of the mitochondrial matrix c. to bring the reducing equivalents of NADH into the mitochondrial matrix since the NADH cannot bypass the membrane itself d. to bring the reducing equivalents of NADH to the electron transport chain since the NADH cannot bypass the membrane itslef e. because the malate-aspartate shuttle is not responcive to FADH2

c. to bring the reducing equivalents of NADH into the mitochondrial matrix since the NADH cannot bypass the membrane itself

16. Why is the malate-aspartate shuttle necessary for oxidative phophorylation in the liver? a. to bring malate into the mitochonrial matrix b. to bring aspartate out of the mitochondrial matrix c. to bring the reducing equivalent of NADH into the mitochondrial matrix since the NADH cannot bypass the membrane itself d. to convert oxaloacetate into malate e. to convery glutamate into a-ketoglutarate

c. to bring the reducing equivalents of NADH into the mitochondrial matrix since the NADH cannoth bypass the membrane itself

5. Succinate dehydrogenase is dysfunctional in a species of garden slug. While its metabolism is compromised on a number of levels, it can still undergo oxidative phosphorylation. What is the maximal P/O ratio for these organisms if NADH is used as an electron source? a. 1 b. 1.5 c. 2 d. 2.5 e. 4

d. 2.5

7. Shuttles are used to transport reducing equivalents and molecules, which themselves have no specific transporter, through the inner mitochondrial membrane. Which molecule cannot move through the membrane directly? a. pyruvate b. b. malate c. glutamate d. a-ketoglutarate e. oxaloacetate

d. a-ketoglutarate

12. What specific lipid is a critical component of the inner mitochondrial membrane, necessary for function of the electron transport chain? a. plasmalogen b. diacylglycerol c. lactosylceramide d. cardiolipin e. phosphatidylinositol

d. cardiolipin

9. What is the "reaction" produced by a photochemical reaction center? a. hydration b. a reduction of the pigment c. dehydrogenation of the pigment d. oxidation of the pigment e. transfer of a H+ across a membrane

d. oxidation of the pigment

8. Which chemical feature is common among photopigments and essential for resonance energy transfer? a. a long, saturated hydrocarbon b. amphipathic c. a protoporphyrin ring structure d. a complete lack of polar groups, which would lead to loss of photon energy e. a ring with at least one double bond

e. a ring with at lease one double bound

15. How is production of reactive oxygen species (ROS) controlled? a. through increased ADP content in the matrix b. through an increase in the NAD+/NADH ration c. with express superoxide dismutase d. with express glutathione peroxidase e. all are correct

e. all are correct

18. How is oxidative phosphorylation inhibited during anaerobic conditions? a. a lack of terminal electron acceptor blocks the electron-transport chain b. ADP levels decrease c. a buildup of glycolytic products (pyruvic acid, lactic acid) lowers pH d. inhibitory protein IF1 becomes functionally dimeric under acidic conditions and binds the ATP synthase inhibiting it e. all are correct

e. all are correct

10. Which of the following is an important source of the H+ used to construct the electrochemical gradient in the thylakoid lument of chloroplasts? a. chlorophyll a and b b. P680 and P700 c. ferridoxin d. NADPH e. oxygen-evolving complex

e. oxygen-evolving complex