Metabolism Practice Exam 4 MCB2010 PDF

Practice exam 4 MCB2010 Instructor: Dr. Ron Ortenberg TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 1) Although most metabolic reactions are freely reversible, a few irreversible catabolic 1) _____ steps are bypassed during biosynthesis...

Practice exam 4 MCB2010 Instructor: Dr. Ron Ortenberg TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 1) Although most metabolic reactions are freely reversible, a few irreversible catabolic 1) _____ steps are bypassed during biosynthesis with special enzymes that catalyze the reverse reaction in order to allow for independent regulation of catabolic and anabolic pathways. SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 2) ________ pathways are those that function both catabolically and anabolically. 2) __________ 3) ________ ________ is a process that can completely catabolize an organic 3) __________ energy source to CO2 using the glycolytic pathways and TCA cycle with O2 as the terminal electron acceptor for an electron transport chain. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 4) The net gain of ATP per molecule of glucose metabolized anaerobically via the 4) _____ Embden-Meyerhof pathway in prokaryotes is ________. A) 36 B) 85 C) 38 D) 2 5) The net gain of ATP per molecule of glucose metabolized to pyruvate using Entner- 5) _____ Doudoroff pathway is ________. A) 1 B) 4 C) 2 D) 0 6) The synthesis of ATP from ADP and Pi, when coupled with an exergonic chemical 6) _____ reaction is called ________ phosphorylation. A) conformational change B) chemiosmotic C) oxidative D) substrate-level SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 7) After glycolysis, pyruvate is oxidized to one CO and the two-carbon molecule 7) __________ 2 acetyl-CoA by a multienzyme system called the ________ ________ complex. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 8) The major function(s) of the TCA cycle is(are) ________. 8) _____ A) energy production B) electron transport C) provision of carbon skeletons for biosynthesis of cell components D) energy production and provision of carbon skeletons for biosynthesis of cell components 9) Production of ATP using the energy liberated when electrons from reduced chemical 9) _____ bonds are passed through the electron transport system is generally referred to as ________. A) substrate-level B) chemiosmotic C) respiration D) conformational change 10) Which of the following is NOT true regarding ATP synthases? 10) _____ A) The subunits of ATP synthase undergo conformational changes during ATP production. B) They span the inner membrane of mitochondria. C) The proton flow is outward during ATP synthesis. D) They require proton motive force to make ATP. 11) Mitochondrial electron transport takes place ________. 11) _____ A) on the outer mitochondrial membrane and on the inner mitochondrial membrane B) in the fluid matrix of the mitochondria C) on the outer mitochondrial membrane D) on the inner mitochondrial membrane 12) In aerobic conditions, it takes ________ sugar to produce the same amount of ATP when 12) _____ compared to anaerobic conditions. A) the same amount of B) more C) less 13) Fatty acids are metabolized by the ________ pathway. 13) _____ A) alpha-oxidation B) delta-oxidation C) beta-oxidation D) gamma-oxidation 14) During breakdown of fatty acids, carbons are removed ________ at a time with each 14) _____ turn of the cycle, and two carbon units are released as ________. A) one; carbon dioxide B) two; acetyl-CoA C) one; methane D) two; ethanol 15) Amino acids are processed first by the removal of the amino group through ________. 15) _____ A) phosphorolytic cleavage B) transamination C) deamination D) deamination or transamination 16) Which of the following may be used as sources of energy by chemolithotrophs? 16) _____ A) Reduced nitrogen compounds B) Hydrogen gas C) Reduced sulfur compounds D) All of the choices are correct. TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 17) All prokaryotic photosynthesizers are anoxygenic. 17) _____ MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 18) Which of the following is the best description of a precursor metabolite? 18) _____ A) A carbon skeleton used as a starting substrate B) A macromolecule consumed in the first steps of metabolism C) An enzyme that is reduced in a metabolic reaction D) An intermediate in the formation of cursor metabolites 19) ________ reactions are used to replace TCA cycle intermediates that have been used to 19) _____ provide carbon skeletons for amino acid biosynthesis. A) Amphibolic B) Anabolic C) Anaplerotic D) Catabolic 20) Photoautotrophs use light energy directly for ________. 20) _____ A) the production of ATP and NADPH B) neither the production of ATP and NADPH nor the reduction of carbon dioxide to glucose C) the reduction of carbon dioxide to glucose D) both the production of ATP and NADPH and the reduction of carbon dioxide to glucose 21) Which of the following is a source of carbon skeletons that are used in the synthesis of 21) _____ amino acids? A) TCA cycle intermediates B) Glycolysis intermediates  C) Acetyl-CoA D) All of the choices are correct. 22) Synthesis of complex molecules from simpler ones with the input of energy is 22) _____ called __________. A) amphibolism B) metabolism C) anabolism D) catabolism 23) Mixed acid fermentation 23) _____ A) occurs in all bacteria. B) produces butyric acid. C) is seen in Streptococcus and Lactobacillus. D) produces several different acids plus CO and H gases. 2 2 E) also produces ethanol. 24) In what ways are oxidative phosphorylation and photophosphorylation similar? 24) _____ A) The source of energy is highly reduced organic compounds B) An electron transport chain is used C) Water is split to provide electrons D) ATP synthase enzyme phosphorylates ADP to make ATP E) Proton motive force is generated 25) What enzymes hydrolyze proteins, releasing amino acids? 25) _____ A) Proteases B) Tranaminases C) Decarboxylases D) Deaminases 26) The amount of ATP produced during anaerobic respiration is ________ that produced 26) _____ during aerobic respiration, because the difference in the standard reduction potential between NADH and the final electron acceptor is ________. A) less than; smaller B) less than; larger C) greater than; smaller D) greater than; larger 27) Indicate the processes below that represent the basic types of chemoorganotrophic 27) _____ metabolism. A) Photosynthesis B) Anaerobic respiration C) Fermentation D) Oxidation-reduction E) Aerobic respiration 28) Processes that supply ATP, reducing power, and precursor metabolites are collectively 28) _____ referred to as ________ reactions. A) redox B) fueling C) generating D) synthetic 29) A newly described bacterial species has been shown to use CO as its carbon source. Its 29) _____ 2 energy source and its source of reducing power (electrons) are inorganic chemicals. Which term would best describe this nutritional type? A) Chemolithoheterotroph B) Photolithoheterotroph C) Photoorganoheterotroph D) Chemolithoautotroph  1) TRUE 2) Amphibolic 3) Aerobic respiration 4) D 5) A 6) D 7) pyruvate dehydrogenase 8) D 9) C 10) C 11) D 12) C 13) C 14) B 15) D 16) D 17) FALSE 18) A 19) C 20) A 21) D 22) C 23) D 24) B, D, E 25) A 26) A 27) B, C, E 28) B 29) D