(Solved): 43. The above reaction (NADH donating its electrons directly to the electron transport chain) takes ...

43. The above reaction (NADH donating its electrons directly to the electron transport chain) takes place in which of the following eukaryotic cell locations? A. the inner mitochondrial membrane B. the thylakoid membrane of chloroplasts C. the chloroplast stroma D. the mitochondrial matrix E. the cytoplasm 44. One example of a stage 1 reaction in the heterotrophic breakdown of food molecules is: A. the intracellular digestion of some amino acids into ${\mathrm{NH}}_4^{+}$and pyruvate B. the intramitochondrial digestion of fatty acids into carbon dioxide and water C. the extracellular digestion of triglycerides into fatty acids and glycerol D. the intramitochondrial digestion of pyruvate into carbon dioxide and water E. the intracellular digestion of glucose monomers into pyruvate 45. Which of the following enzymes consumes one molecule of NADH, during anaerobic fermentation in humans, as it converts a three-carbon substrate molecule into a three-carbon product molecule? A. succinate dehydrogenase B. pyruvate decarboxylase C. isocitrate dehydrogenase D. lactate dehydrogenase E. alcohol dehydrogenase 46. Which electrically-neutral molecules are generated when complex IV (of the mitochondrial electron transport chain) adds 4 electrons and 4 protons to one molecule of diatomic oxygen gas? A. two molecules of hydrogen peroxide B. two molecules of the superoxide free radical C. two molecules of the hydroxide ion D. two molecules of the hydroxyl free radical E. two molecules of water 47. The anaerobic, chemoautotrophic archaeobacterium Methanococcus jannaschii uses which of the following carbon-fixation pathways to obtain organic carbon from ${\mathrm{CO}}_2$ ? A. the Wood-Ljungdahl pathway B. oxygenic photosynthesis C. the Hill reaction D. the Calvin cycle