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Glycolysis is believed to be one of the most ancient of metabolic processes. Which statement below LEAST supports this idea? a. If run in reverse, glycolysis will build glucose molecules. b. Glycolysis neither uses nor needs oxygen. c. Glycolysis is found in all eukaryotic cells. d. The enzymes of glycolysis are found in the cytosol rather than in a membrane enclosed organelle. e. Bacteria, the most primitive of cells, make extensive use of glycolysis. Answer: a The direct energy source that drives ATP synthesis during respiratory oxidative phosphorylation is a. oxidation of glucose to carbon dioxide and water. b. the thermodynamically favorable flow of electrons from NADH to the mitochondrial electron transport carriers. c. the final transfer of electrons to oxygen d. the difference in H+ concentration on opposite sides of the mitochondrial membrane e. thermodynamically favorable transfer of phosphate from glycolysis and Krebs cycle intermediate molecules of ADP Answer: d Pyruvate is the last product of glycolysis. Which statement below is TRUE? a. There is more energy in 6 molecules of carbon dioxide than in 2 molecules of pyruvate. b. There is more energy in pyruvate than lactate. c. There is less energy in 2 molecules of pyruvate than in 1 molecule of glucose. d. Pyruvate is in a more oxidized state than carbon dioxide. e. Pyruvate is in a more reduced state than glucose. Answer: c A major function of the mitochondrial membrane is the conversion of energy from electrons to the stored energy of the phosphate bond in ATP. To accomplish this function, this membrane must have all of the following features EXCEPT a. proteins to accept electrons from NADH. b. integral, transverse ATP synthase. c. proton pumps embedded in the membrane. d. the electron transport chain of proteins. e. high permeability to protons. Answer: e If citric acid has 6 carbon atoms, how many carbon atoms does succinic acid have? a. 1 b. 4 c. 5 d. 6 e. 12 Answer: b Starting with one acetyl CoA molecule, what is the maximum number of ATP molecules that could be made through substrate-level phosphorylation? a. 1 b. 2 c. 11 d. 12 e. more than 20 Answer: a All of the following substances are produced in a muscle cell under anaerobic conditions EXCEPT a. ATP b. pyruvate c. lactate d. acetyl CoA e. NADH Answer: d Refer to the list below for this question . A. Stage 1: glycolysis B. Stage 2: oxidation of pyruvate to acteyl CoA C. Stage 3: Krebs cycle D. Stage 4: oxidative phophorylation (chemiosmosis) Carbon dioxide is released during which stage(s)? a. stage 3 only b. stages 2 and 3 c. stages 3 and 4 d. stages 1, 2, and 3 e. stages 2, 3, and 4 Answer: b Suppose a yeast cell uses 10 moles of glucose for energy production. No oxygen is available. What will be the maximum net yield of ATP in moles? a. 12 b. 15 c. 20 d. 30 e. 36 Answer: c Catabolism of proteins, lipids, and carbohydrates can result in a 2-carbon molecule that enters the Krebs cycle. What is the molecule? a. glucose b. acetic acid or acetyl CoA c. a fatty acid d. an amino acid e. pyruvate Answer: b You have a friend who lost 15 pounds of fat on a diet. Where did the fat go (how was it lost)? a. It was lost as CO2 and H2O. b. Chemical energy was converted to heat and then released. c. It was converted to ATP, which weighs less than fat. d. It was broken down to amino acids and eliminated from the body. e. It was converted to urine and eliminated from the body. Answer: a If both the inner and outer mitochondrial membranes were punctured, which of the following processes would be least affected? a. glycolysis b. oxidation of pyruvate to acetyl CoA c. Krebs cycle d. chemiosmosis Answer: a A sprig of elodea is placed in a bromthymol blue solution. After a few hour in the dark, the solution turns yellow. The purpose of this experiment is to show that a. oxygen is given off during photosyntheis. b. carbon dioxide is used during photosynthesis. c. oxygen is used during respiration. d. carbon dioxide is given off during respiration. e. oxygen is given off during respiration. Answer: d Which of the following is NOT true concerning the cellular compartmentalization of the steps of respiration or fermentation? a. Acetyl CoA is produced only in the mitochondria b. lactate is produced only in the cytosol c. NADH is produced only in the mitochondria d. FADH2 is produced only in the mitochondria e. ATP is produced in the cytosol and the mitochondria Answer: c In the mesophyll cell of a leaf, the synthesis of ATP occurs in which of the following? I. Ribosomes II. Mitochondria III. Chloroplasts a. I only b. II only c. III only d. II and III only e. I, II, and III Answer: d This diagram depicts chemiosmosis in a chloroplast. What is occurring at “Q”? Answer: e a. Energy is consumed. b. Water is cleaved. c. NADP+ is reduced. d. ADP is phosphorylated to ATP e. Electrons are transported down the electron transport chain. A study of the metabolic rate in a terrestrial community shows that the energy captured in photosynthesis exceeds the energy released by respiration. Which of the following situations is occurring? a. Community biomass is increasing. b. Community biomass is decreasing. c. A climax community has been reached. d. The first law of thermodynamics is not in effect. e. The second law of thermodynamics is not in effect. Answer: a A biologist isolates numerous, tiny, green-pigmented cells from a sample of lake water. The cells are covered with a mucilaginous sheath. They contain relatively large amounts of chlorophyll a and phycobilin pigments and lack a compact, organized nucleus. electron microscopy reveals that these cells also contain which of the following pairs of subcellular structures? a. ribosomes and chloroplasts b. ribosomes and mitochondria c. golgi bodies and a cell wall d. thylakoids and a cell wall e. chloroplasts and mitochondria Answer: d Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes? a. the splitting of water b. the absorption of light energy by chlorophyll c. The flow of electrons from PSII to PSI d. The synthesis of ATP e. The reduction of NADP+ Answer: d The reactions of the Calvin cycle require all of the following EXCEPT: a. CO2 b. ATP c. RuBP d. glucose e. NADPH Answer: d All the events listed below occur in the energy-capturing light reactions of photosynthesis EXCEPT: a. oxygen is produced b. NADP+ is reduced to NADPH c. carbon dioxide is incorporated into PGA d. ADP is phosphorylated to yield ATP e. light is absorbed and funneled to a reaction center chlorophyll a Answer: c Which of the following is NOT true of RuBP carboxylase? a. It is a protein. b. It speeds up a chemical reaction. c. It lowers the energy of activation. d. It catalyzes a phosphorylation reaction. e. It has an affinity for both O2 and CO2. Answer: d Why is the absorption spectrum different from the action spectrum? a. Green and yellow wavelengths inhibit the absorption of red and blue wavelengths. b. Bright sunlight destroys photosynthetic pigments. c. The two lines are probably the result of inaccurate measurements. d.Other pigments absorb light in addition to chlorophyll a e. Anaerobic bacteria probably interfered with light absorption. Answer: d From the action spectrum we can correctly conclude that a. Chlorophyll absorbs more green light than red light b. Plants can use all colors of visible light for photosynthesis. c. Every color of light is equally good for photosynthesis. d. Light in the green range produces the most effective photosynthesis. e. There are two independent photosystems in leaves; one for red light alone and one for blue light alone. Answer: b Where does the Calvin cycle of photosynthesis take place? a. stroma of the chloroplast b. thylakoid membrane c. cytoplasm surrounding the chloroplast d. chlorophyll molecule e. outer membrane of chloroplasts Answer: a CAM plants keep stomates closed in daytime, thus reducing loss of water. They can do this because they can: a. fix CO2 into organic acids during the night. b. fix CO2 into sugars in the bundle-sheath cells. c. fix CO2 into pyruvic acid in the mesophyll cells. d. use the enzyme phosphofructokinase, which outcompetes rubisco for CO2. e. use PS I and PS II at night. Answer: a In plant cells, ATP is made in response to light. An electron transport chain is involved. This electron transport chain is found in the a. thylakoid membrane of chloroplasts. b. stroma of chloroplasts. c. inner membrane of mitochondria. d. matrix of mitochondria. e. cytoplasm. Answer: a If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (O-18), later analysis will show that all but one of the following compounds produced by the algae contain the O-18 label. That one exception is: a. PGA b. PGAL c. glucose d. RuBP e. O2 Answer: e The process of cyclic photophosphorylation uses light energy to synthesize: a. ADP and ATP b. ATP only c. ATP and NADPH d. ADP and NADPH e. PS I and PSII Answer: b The process of noncyclic photophosphorylation uses light energy to synthesize: a. ADP and ATP b. ATP only c. ATP and NADPH d. ADP and NADPH e. PS I and PSII Answer: c In green plants, the primary function of the Calvin cycle is to: a. use ATP to release carbon dioxide. b. use NADPH to release carbon dioxide. c. split water and release oxygen. d. transport RuBP out of the cytoplasm. e. construct simple sugars from carbon dioxide. Answer: e Which of the following statements best represents the relationships between the light reactions and the Calvin cycle? a. The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, phosphate, and NADP+ to the light reactions. b. The light reactions provide ATP and NADPH to the carbon fixation step of the Calvin cycle, and the cycle provides water and electrons to the light reactions. c. The light reactions supply the Calvin cycle with CO2 to produce sugars, and the Calvin cycle supplies the light reaction with sugars to produce ATP. d. The light reactions provide the Calvin cycle with oxygen for electron flow, and the cycle provides the light reactions with water to split. e. None of the above Answer: a In the thylakoid membranes, what is the main function of the antenna pigment molecules? a.to split water and release oxygen to the reaction center chlorophyll a b. to harvest photons and transfer light energy to the reaction center chlorophyll a c. to synthesize ATP from ADP and phosphate d. to pass electrons to ferredoxin and then NADPH e. to concentrate photons inside the stroma Answer: b In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from: a. the stroma to the chlorophyll. b. the matrix to the stroma. c. the stroma to the thylakoid compartment. d. the intermediate space to the matrix. e. the light reactions to the Calvin cycle. Answer: c Each photosystem: a. contains a mix of chlorophylls and carotenoids. b. has a light gathering antenna complex. c. has a special chlorophyll a molecule in the reaction center. d. All three are correct. Answer: d Molecule “A” Which of the following is true of molecule “A”? a. It is classified as a carotenoid. b. It would move the furthest of all the plant pigments in chromatography using a nonpolar solvent such as petroleum ether. c. It is found embedded in the thylakoid membrane of the chloroplast. Answer: c d. It contains iron. e. It is required for the contraction of muscles.