Biology Questions on Cellular Respiration (PDF)

1. Which of the following correctly states the relationship between anabolic and catabolic pathways? A) Anabolic pathways synthesize more complex organic molecules using the energy derived from catabolic pathways. B) The flow of energy between catabolic and anabolic pathways is reversible. C) Ene...

1. Which of the following correctly states the relationship between anabolic and catabolic pathways? A) Anabolic pathways synthesize more complex organic molecules using the energy derived from catabolic pathways. B) The flow of energy between catabolic and anabolic pathways is reversible. C) Energy derived from catabolic pathways is used to drive the breakdown of organic molecules in anabolic pathways. D) Catabolic pathways produce usable cellular energy by synthesizing more complex organic molecules. Correct Answer: A 2. Organisms are described as thermodynamically open systems. Which of the following statements is consistent with this description? A) Organisms acquire energy from and lose energy to their surroundings. B) The metabolism of an organism is isolated from its surroundings. C) Because energy must be conserved, organisms constantly recycle energy and thus need no input of energy. D) Heat produced by the organism is conserved in the organism and not lost to the environment. Correct Answer: A 3. Which of the following states the relevance of the first law of thermodynamics to biology? A) Energy is destroyed as glucose is broken down during cellular respiration. B) Photosynthetic organisms produce energy in sugars from sunlight. C) Energy can be freely transformed among different forms as long as the total energy is conserved. D) Living organisms must increase the entropy of their surroundings. Correct Answer: C 4. According to the second law of thermodynamics, which of the following is true? A) Energy conversions increase the order in the universe. B) All reactions produce some heat. C) The decrease in entropy associated with life must be compensated for by increased entropy in the environment in which life exists. D) The entropy of the universe is constantly decreasing. Correct Answer: C 5. If the entropy of a living organism is decreasing, which of the following is most likely to be occurring simultaneously? A) The first law of thermodynamics is being violated. B) Heat is being used by the organism as a source of energy. C) Energy input into the organism must be occurring to drive the decrease in entropy. D) The entropy of the organism's environment must also be decreasing. Correct Answer: C 6. If, during a process, the system becomes more ordered, then __________. A) ΔG is positive B) ΔG is negative C) ΔH is negative D) ΔS is negative Correct Answer: D 7. An exergonic (spontaneous) reaction is a chemical reaction that __________. A) Leads to a decrease in the entropy of the universe B) Is common in anabolic pathways C) Occurs only when an enzyme or other catalyst is present D) Releases energy when proceeding in the forward direction Correct Answer: D 8. The free energy derived from the hydrolysis of ATP can be used to perform many kinds of cellular work. Which of the following is an example of the cellular work involved in the production of electrochemical gradients? A) Chromosome movement on microtubules B) The chemical synthesis of ATP C) The beating of cilia D) Proton movement against a gradient of protons Correct Answer: D 9. In general, the hydrolysis of ATP drives cellular work by __________. A) Releasing heat B) Releasing free energy that can be coupled to other reactions C) Lowering the activation energy of the reaction D) Acting as a catalyst Correct Answer: B 10. How do enzymes lower activation energy? A) By increasing the reactivity of products B) By locally concentrating the reactants C) By harnessing heat energy to drive the breakage of bonds between atoms D) The first two responses are correct. Correct Answer: D 11. A molecule becomes more oxidized when it __________. A) Loses a hydrogen (H+) ion B) Changes shape C) Gains a hydrogen (H+) ion D) Gains an electron E) Loses an electron Correct Answer: E 12. In the overall process of glycolysis and cellular respiration, __________ is oxidized and __________ is reduced. A) Carbon dioxide; water B) ATP; oxygen C) Oxygen; ATP D) Glucose; oxygen E) Glucose; ATP Correct Answer: D 13. Most of the ATP produced in cellular respiration comes from which of the following processes? A) Glycolysis B) Substrate-level phosphorylation C) Oxidative phosphorylation D) The citric acid cycle E) Reduction of NADH Correct Answer: C 14. The function of cellular respiration is to __________. A) Produce carbohydrates B) Extract CO2 from the atmosphere C) Reduce CO2 D) Synthesize macromolecules from monomers E) Extract usable energy from glucose Correct Answer: E 15. A small amount of ATP is made in glycolysis by which of the following processes? A) Transfer of electrons and hydrogen atoms to NAD+ B) Transport of electrons through a series of carriers C) Transfer of a phosphate group from a fragment of glucose to ADP by substrate-level phosphorylation D) Attachment of a free inorganic phosphate (Pi) group to ADP to make ATP E) Harnessing energy from the sun Correct Answer: C 16. Where do the reactions of glycolysis occur in a eukaryotic cell? A) Across the inner membrane of the mitochondrion B) The cytosol C) The inner membrane of the mitochondrion D) In the intermembrane space of the mitochondrion E) The matrix of the mitochondrion Correct Answer: B 17. In an experiment, mice were fed glucose (C6H12O6) containing a small amount of radioactive oxygen. The mice were closely monitored, and after a few minutes, radioactive oxygen atoms showed up in __________. A) Oxygen gas B) ATP C) Water D) NADH E) Carbon dioxide Correct Answer: E 18. The energy given up by electrons as they move through the electron transport chain is used in which of the following processes? A) The production of NADH and FADH2 B) The breakdown of glucose C) The oxidation of water D) The production of CO2 E) Pumping H+ across a membrane Correct Answer: E 19. Energy for synthesizing ATP is obtained by ATP synthase directly from which of the following processes? A) The oxidation of glucose B) The flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme C) The movement of electrons through a series of carriers D) The reduction of oxygen E) The oxidation of NADH and FADH2 Correct Answer: B 20. During aerobic respiration, molecular oxygen (O2) is used for which of the following purposes? A) At the end of glycolysis to oxidize pyruvate B) Between glycolysis and the citric acid cycle to split a carbon from pyruvate, producing CO2 C) At the end of the electron transport chain to accept electrons and form H2O D) At the end of the citric acid cycle to regenerate citric acid E) As a source of O2 in every reaction that produces CO2 Correct Answer: C 21. In photosynthesis, plants use carbon from __________ to make sugar and other organic molecules. A) Chlorophyll B) Soil C) Carbon dioxide D) The sun Correct Answer: C 22. How does carbon dioxide (CO₂) enter the leaf? A) Through the roots B) Through the chloroplasts C) Through the stomata D) Through the thylakoids E) Through the vascular system Correct Answer: C 23. Chlorophyll molecules are in which part of the chloroplast? A) Stomata B) Plasma membrane C) Thylakoid membranes D) Stroma Correct Answer: C 24. The source of the oxygen produced by photosynthesis has been identified through experiments using radioactive tracers. The oxygen comes from __________. A) Light B) Water C) Carbon dioxide D) Glucose Correct Answer: B 25. The Calvin cycle occurs in the __________. A) Thylakoid membrane B) Stomata C) Stroma D) Thylakoid lumen Correct Answer: C 26. Molecular oxygen is produced during __________. A) Stomatal opening B) The Calvin cycle C) Cyclic electron flow during the light reactions D) Linear electron flow during the light reactions Correct Answer: D 27. When chloroplast pigments absorb light, __________. A) The pigments lose potential energy B) The Calvin cycle is triggered C) The pigments’ electrons become excited D) The pigments’ photons become excited Correct Answer: C 28. Where do the electrons entering photosystem II come from? A) ATP B) The electron transport chain C) Light D) Water Correct Answer: D 29. During photosynthesis in chloroplasts, O₂ is produced from __________ via a series of reactions associated with __________. A) CO₂; photosystem II B) H₂O; photosystem II C) CO₂; the Calvin cycle D) H₂O; photosystem I Correct Answer: B 30. The light reactions of photosynthesis generate high-energy electrons, which end up in __________ through linear electron flow. The light reactions also produce __________ and __________. A) Oxygen; sugar; ATP B) Water; sugar; oxygen C) NADPH; ATP; oxygen D) ATP; NADPH; oxygen Correct Answer: C