UTSC BIOA01 Life on Earth TERM TEST #1 60 PRACTICE QUESTIONS AND ANSWERS 2024

UTSC BIOA01 Life on Earth TERM TEST #1 60 PRACTICE QUESTIONS AND ANSWERS 2024 Here are 60 Practice Questions so you can have an idea of the kind of questions that are likely to be asked on Term Test # 1. 1. Which of the following is a correct sequence for the biological classification of organisms? A. genus, species, family, order, class, phylum, kingdom B. genus, species, family, order, class, kingdom, phylum C. genus, species, order, family, class, phylum, kingdom D. species, genus, order, family, class, kingdom, phylum E. species, genus, family, order, class, phylum, kingdom 2. Which structure is common to plant and animal cells? A. chloroplast B. wall made of cellulose C. central vacuole D. mitochondrion E. centriole 3. Which of the following is true for all exergonic reactions? A. The products have more total energy than the reactants. B. The reaction proceeds with a net release of free energy. C. Some reactants will be converted to products. D. A net input of energy from the surroundings is required for the reactions to proceed. E. The reactions are non-spontaneous. 4. Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly? A. CO2 B. an amino acid C. glucose D. K+ E. starch 5. Which of the following statements describes NAD+? A. NAD+ has more chemical energy than NADH+H+. B. NAD+ is reduced to NADH+H+ during both glycolysis and the citric acid cycle. C. NAD+ is reduced by the action of hydrogenases. D. NAD+ can donate electrons for use in substrate-level phosphorylation. E. In the absence of NAD+, glycolysis can still function. 6. In what way do the membranes of a eukaryotic cell vary? A. Certain proteins are unique to each membrane. B. Phospholipids are found only in certain membranes. C. Only certain membranes of the cell are selectively permeable. D. Only certain membranes are constructed from amphipathic molecules. E. Some membranes have hydrophobic surfaces exposed to the cytoplasm, while others have hydrophilic surfaces facing the cytoplasm. 7. Members of the domains Bacteria and Archaea A. have nuclei. B. are multicellular. C. have chloroplasts. D. are prokaryotes. E. have flagella. 8. Which of the following metabolic processes can occur without a net influx of energy from some other process? A. ADP + Pi → ATP + H2O B. C6H12O6 + 6 O2 → 6 CO2 + 6 H2O C. 6 CO2 + 6 H2O → C6H12O6 + 6 O2 D. amino acids → protein E. glucose + fructose → sucrose 9. Most cells cannot harness heat to perform work because A. heat is not a form of energy. B. cells do not have much heat; they are relatively cool. C. temperature is usually uniform throughout a cell. D. heat can never be used to do work. E. heat denatures enzymes. 10. According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly A. spread in a continuous layer over the inner and outer surfaces of the membrane. B. confined to the hydrophobic core of the membrane. C. embedded in a lipid bilayer. D. randomly oriented in the membrane, with no fixed inside-outside polarity. E. free to depart from the fluid membrane and dissolve in the surrounding solution. 11. Most CO2 from catabolism is released during A. glycolysis. B. lactate fermentation. C. the citric acid cycle. D. electron transport. E. oxidative phosphorylation. 12. The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is A. the oxidation of glucose and other organic compounds. B. the flow of electrons down the electron transport chain. C. the affinity of oxygen for electrons. + D. the H concentration gradient across the inner mitochondrial membrane. E. the transfer of phosphate to ADP. 13. Some bacteria are metabolically active in hot springs because A. they are able to maintain a cooler internal temperature. B. high temperatures make catalysis unnecessary. C. their enzymes have high optimal temperatures. D. their enzymes are completely insensitive to temperature. E. they use molecules other than proteins or RNAs as their main catalysts. 14. Which of the following factors would tend to increase membrane fluidity? A. a greater proportion of unsaturated phospholipids B. a greater proportion of saturated phospholipids C. a lower temperature D. a relatively high protein content in the membrane E. a greater proportion of relatively large glycolipids compared with lipids having smaller molecular masses 15. What is the reducing agent (or electron donor) in the following reaction? A. oxygen B. NADH+H+ + + Pyruvate + NADH + H + → Lactate + NAD C. NAD D. lactate E. pyruvate 16. Reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reaction's A. entropy. B. activation energy. C. endothermic level. D. heat content. E. free-energy content. 17. What does the chemiosmotic process in mitochondria involve? A. establishment of a proton gradient B. diffusion of electrons through the thylakoid membrane C. reduction of water to produce ATP energy D. movement of water by osmosis into the intermembrane space from the matrix E. oxidation of glucose, releasing carbon dioxide, NADH+H+, and FADH2 18. Which of the following processes includes all others? A. osmosis B. diffusion of a solute across a membrane C. facilitated diffusion D. passive transport E. transport of an ion down its electrochemical gradient 19. Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as is to . A. exergonic; spontaneous B. exergonic; endergonic C. free energy; entropy D. work; energy E. entropy; enthalpy 20. Active transport involves all of the following except the A. diffusion of solute through the lipid bilayer of a membrane. B. transport of solute against a concentration gradient. C. a specific transport protein in the membrane. D. pumping of solutes across the membrane. E. hydrolysis of ATP. 21. When electrons move closer to a more electronegative atom, what happens? A. Energy is released. B. Energy is consumed. C. The more electronegative atom is reduced. D. The more electronegative atom is oxidized. E. A and C are correct. 22. If an enzyme solution is saturated with substrate, the most effective way to obtain a faster yield of products is to A. add more substrate. B. add more of the enzyme. C. heat the solution to 90°C. D. add an allosteric inhibitor. E. add a noncompetitive inhibitor. 23. Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule? A. the citric acid cycle B. the electron transport chain C. glycolysis D. synthesis of acetyl CoA from pyruvate E. reduction of pyruvate to lactate 24. If an enzyme is added to a solution where its substrate and product are in equilibrium, what would occur? A. Additional product would be formed. B. Additional substrate would be formed. C. The reaction would change from endergonic to exergonic. D. The free energy of the system would change. E. Nothing; the reaction would stay at equilibrium. 25. Which reaction would prevail if both Q and S were present in the cell in high concentrations? A. L → M B. M → O C. L → N D. O → P E. R → S 26. In mitochondria, exergonic redox reactions A. are the source of energy driving prokaryotic ATP synthesis. B. are directly coupled to substrate-level phosphorylation. C. provide the energy that establishes the proton gradient. D. reduce carbon atoms to carbon dioxide. E. are coupled via phosphorylated intermediates to endergonic processes. 27. Which of the following statements is true concerning catabolic pathways? A. They are endergonic. B. They are spontaneous and do not need enzyme catalysis. C. They combine molecules into more energy-rich molecules. D. They build up complex molecules such as protein from simpler compounds. E. They are coupled with anabolic pathways to which they supply energy in the form of ATP. 28. Which of the following is a true distinction between fermentation and cellular respiration? A. Only respiration oxidizes glucose. B. NADH is oxidized by the electron transport chain in respiration only. C. Substrate-level phosphorylation is unique to fermentation. D. Fermentation, but not respiration, is an example of a catabolic pathway. + E. NAD functions as an oxidizing agent only in respiration. 29. Which of the following is a statement of the first law of thermodynamics? A. Energy cannot be created or destroyed. B. The entropy of the universe is decreasing. C. Kinetic energy is stored energy that results from the specific arrangement of matter. D. The entropy of the universe is constant. E. Energy cannot be transferred or transformed. 30. When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction reaction, the molecule becomes A. dehydrogenated. B. hydrogenated. C. reduced. D. oxidized. E. an oxidizing agent. 31. Which type of bond must be broken for water to vaporize? A. ionic bonds B. nonpolar covalent bonds C. polar covalent bonds D. hydrogen bonds E. covalent bonds 32. Where does glycolysis takes place? A. mitochondrial matrix B. mitochondrial outer membrane C. mitochondrial inner membrane D. mitochondrial intermembrane space E. cytosol 33. What must be the difference (if any) between the structure of ATP and the structure of the precursor of the A nucleotide in RNA? A. The sugar molecule is different. B. The nitrogen-containing base is different. C. The number of phosphates is three instead of one. D. The number of phosphates is three instead of two. E. There is no difference. 34. Which of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the removal of a carbon (CO2) from one molecule of pyruvate? A. lactate B. oxaloacetate C. glyceraldehydes-3-phosphate D. acetyl CoA E. citrate 35. When two atoms are equally electronegative, what type of bond will form? A. hydrophobic B. polar covalent C. ionic D. nonpolar covalent E. hydrogen 36. There are 20 different amino acids. What makes one amino acid different from another? A. different carboxyl groups attached to an alpha-carbon B. different amino groups attached to an alpha-carbon C. different side chains (R groups) attached to an alpha-carbon D. different alpha-carbons E. different asymmetric carbons 37. How many carbon atoms are fed into the citric acid cycle as a result of the oxidation of one molecule of pyruvate? A. 2 B. 4 C. 6 D. 8 E. 10 38. When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated? A. It is used to power yet more cellular work. B. It is transported to specific organs such as the brain. C. It is used to store energy as more ATP. D. It is used to generate ADP from nucleotide precursors. E. It is lost to the environment. 39. The final electron acceptor of the electron transport chain that functions in aerobic oxidative phosphorylation is A. oxygen. B. water. C. NAD+. D. pyruvate. E. ADP. 40. Which of the following is the correct order (listed in decreasing order) for the relative strengths of chemical bonds in biological molecules? A. covalent, ionic, hydrogen, van der Waals forces B. ionic, covalent, hydrogen, van der Waals forces C. hydrogen, covalent, van der Waals forces, ionic D. ionic, covalent, van der Waals forces, hydrogen E. covalent, van der Waals forces, hydrogen, ionic 41. Reduction of NAD+ occurs during A. photosynthesis. B. respiration. C. both photosynthesis and respiration. D. neither photosynthesis nor respiration. E. photorespiration. 42. Whenever energy is transformed, there is always an increase in the A. free energy of the system. B. free energy of the universe. C. entropy of the system. D. entropy of the universe. E. enthalpy of the universe. 43. In glycolysis, for each molecule of glucose oxidized to pyruvate A. 2 molecules of ATP are used and 2 molecules of ATP are produced. B. 2 molecules of ATP are used and 4 molecules of ATP are produced. C. 4 molecules of ATP are used and 2 molecules of ATP are produced. D. 2 molecules of ATP are used and 6 molecules of ATP are produced. E. 6 molecules of ATP are used and 6 molecules of ATP are produced. 44. Which of the following properties or processes do we associate with living things? A. evolutionary adaptations B. energy processing C. responding to the environment D. growth and reproduction E. all of the above 45. Which of the following is not a theme that unifies biology? A. interaction with the environment B. emergent properties C. evolution D. reductionism E. structure and function 46. Where is free energy released during the electron transport chain of cellular respiration? A. Only at the end, when O2 is converted to H2O. B. Each time a carrier is oxidized. C. Only at the beginning, when NADH+H+ is converted to NAD+. D. Each time a carrier is reduced. E. Only when FADH2 is converted to FAD. 47. Which term includes all others in the list? A. monosaccharide B. disaccharide C. starch D. carbohydrate E. polysaccharide 48. Which of the following statements describes NAD+? A. NAD+ is reduced to NADH + H+ during both glycolysis and the citric acid cycle. B. NAD+ has more chemical energy than NADH + H+. C. NAD+ is reduced by the action of hydrogenases. D. NAD+ can donate electrons for use in substrate- level phosphorylation. E. In the absence of NAD+, glycolysis can still function. 49. When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs? A. The pH of the matrix decreases. B. ATP synthase moves protons by facilitated diffusion. C. The electrons gain free energy. D. The cytochromes phosphorylate ADP to form ATP. E. NAD+ is oxidized. 50. Which of the following statements about glycolysis is false? A. Glycolysis proceeds indefinitely as long as glucose is available. B. The enzymes of glycolysis are located in the cytosol of the cell. C. Glycolysis can operate in the complete absence of O2. D. The end products of glycolysis are ATP, pyruvate and NADH+H+. E. Glycolysis makes ATP through substrate-level phosphorylation. 51. The light reactions of photosynthesis supply the Calvin cycle with A. light energy. B. CO2 and ATP. C. H2O and NADPH. D. ATP and NADPH. E. sugar and O2. 52. Which of the following sequences correctly represents the flow of electrons during photosynthesis? A. NADPH → O2 → CO2 B. H2O → NADPH → Calvin cycle C. NADPH → chlorophyll → Calvin cycle D. H2O → photosystem I → photosystem II E. NADPH → electron transport chain → O2 53. In mechanism, photophosphorylation is most similar to A. substrate-level phosphorylation in glycolysis. B. oxidative phosphorylation in cellular respiration. C. the Calvin cycle. D. carbon fixation. E. reduction of NADP+. 54. How is photosynthesis similar in C4 and CAM plants? A. In both cases, only photosystem I is used. B. Both types of plants make sugar without the Calvin cycle. C. In both cases, Rubisco is not used to fix carbon initially. D. Both types of plants make most of their sugar in the dark. E. In both cases, thylakoids are not involved in photosynthesis. 55. Which of the following does not occur during the Calvin cycle? A. carbon fixation B. oxidation of NADPH C. release of oxygen D. regeneration of the CO2 acceptor E. consumption of ATP 56. Photosynthesis ceases when leaves wilt, mainly because A. the chlorophyll of wilting leaves breaks down. B. flaccid mesophyll cells are incapable of photosynthesis. C. stomata close, preventing CO2 from entering the leaf. D. photolysis, the water-splitting step of photosynthesis, cannot occur when there is a water deficiency. E. accumulation of CO2 in the leaf inhibits enzymes. 57. Active transport involves all of the following except the A. diffusion of solute through the lipid bilayer of a membrane. B. pumping of solutes across the membrane. C. hydrolysis of ATP. D. transport of solute against a concentration gradient. E. a specific transport protein in the membrane. 58. What are the products of the light reactions that are subsequently used by the Calvin cycle? A. oxygen and carbon dioxide B. carbon dioxide and RuBP C. water and carbon D. electrons and photons E. ATP and NADPH 59. Which of the events listed below occur in the light reactions of photosynthesis? A. NADP is produced. B. NADPH is reduced to NADP+. C. carbon dioxide is incorporated into 3PG. D. ATP is phosphorylated to yield ADP. E. light is absorbed and funneled to reaction-center chlorophyll a. 60. In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from A. the stroma to the photosystem II. B. the matrix to the stroma. C. the stroma to the thylakoid space. D. the intermembrane space to the matrix. E. ATP synthase to NADP+ reductase.