Name: ________________________ AP Biology Review Mid-Term Multiple Choice Identify the choice that best completes the statement or answers the question.
. ____
1. When does a hydronium ion form? a. when a water molecule splits in half b. when a hydrogen ion binds with a hydroxide ion c. when two water molecules bind d. as a product of evaporation e. when a water molecule gains an hydrogen ion from another water molecule
____
2. Glycolysis is an ____ reaction. a. endothermic b. unregulated c. exergonic d. endergonic e. abnormal
____
3. Which of these does not contain a structural protein? a. ligaments b. spider silk c. ovalbumin d. muscles e. tendons
____
4. A function of cholesterol that does not harm health is its role a. as the primary male sex hormone. b. as a component of animal cell membranes. c. as the primary female sex hormone. d. in calcium and phosphate metabolism. e. None of the above; all of cholesterol's effects on the body are harmful.
____
5. What property of water is responsible for water transport in plants? a. insulation b. cohesion c. its versatility as a solvent d. moderation of temperature e. its role as a buffer
____
6. How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose? a. 2 b. 8 c. 10 d. 4 e. 6
____
7. The interior of the phospholipid bilayer is a. composed of fatty acids. b. hydrophobic. c. water. d. hydrophilic. e. composed of cholesterol. 1
Name: ________________________
____
8. In the reaction A B + C + heat, a. there is a net input of energy. b. the potential energy of the products is greater than that of the reactant. c. the potential energy of the products is the same as that of the reactant. d. entropy has decreased. e. the potential energy of the products is less than that of the reactant.
____
9. Which of these structures is unique to plant cells? a. mitochondrion b. nucleoid region c. flagellum d. central vacuole e. peroxisome
____
10. In eukaryotic cells, the first step in protein synthesis is the a. linking of nucleotides to form a polypeptide. b. removal of introns from RNA and the stitching together of exons c. transferring of information from DNA to messenger RNA d. translation of an RNA nucleotide sequence into a sequence of amino acids. e. translation of a DNA nucleotide sequence into a sequence of amino acids.
____
11. What name is given to the reactants in an enzymatically catalyzed reaction? a. substrate b. reactors c. EA d. active sites e. products
____
12. The primary structure of a protein is a. composed of two or more polypeptide chains. b. irregular folding. c. an helix or a pleated sheet. d. maintained by hydrogen bonds. e. the amino acid sequence of the polypeptide chain.
____
13. C4 plants differ from C3 and CAM plants in that C4 plants a. use malic acid to transfer carbon dioxide to the Calvin cycle. b. use PEP carboxylase to fix carbon dioxide. c. are better adapted to wet conditions. d. transfer fixed carbon dioxide to cells in which the Calvin cycle occurs. e. open their stomata only at night.
____
14. Hydrocarbons a. are held together by hydrogen bonds. b. are polar. c. are held together by ionic bonds. d. contain only hydrogen and carbon atoms. e. contain nitrogen.
____
15. Pyruvate is formed a. on the inner mitochondrial membrane. b. in the mitochondrial matrix. c. on the outer mitochondrial membrane. d. in the cytosol. e. in the nucleus.
2
Name: ________________________
____
16. In C3 plants the conservation of water promotes a. photosynthesis. b. the light reactions. c. the opening of stomata. d. photorespiration. e. a shift to C4 photosynthesis.
____
17. Which of these is a difference between DNA and RNA? a. DNA contains thymine; RNA contains uracil. b. In DNA, adenine pairs with guanine; in RNA, adenine pairs with thymine. c. DNA is found in the nucleus; RNA is never found in the nucleus. d. DNA consists of five different nucleotides; RNA consists of four different nucleotides. e. RNA is double-stranded; DNA is single-stranded.
____
18. Carbon fixation involves the addition of carbon dioxide to a. 3-PGA. b. RuBP. c. G3P. d. rubisco. e. NADPH.
____
19. ____ is composed of DNA and protein. a. A flagellum b. A ribosome c. A mitochondrion d. A centriole e. Chromatin
____
20. About ____ molecules in a glass of water are dissociated. a. 1 in 5,000,000 b. 1 in 1,000,000,000 c. 1 in 2 d. 1 in 500,000,000 e. 1 in 1,000,000
____
21. Endocytosis moves materials ____ a cell via ____. a. into; a transport protein b. into; membranous vesicles c. into; facilitated diffusion d. out of; diffusion e. out of; membranous vesicles
____
22. A(n) ____ refers to two or more atoms held together by covalent bonds. a. isotope b. ion c. molecule d. community e. shell
____
23. Carbohydrates generally have a molecular formula a. that includes at least one hydrocarbon tail. b. that includes a -NH2 group. c. in which carbon, hydrogen, and oxygen are present in a ratio of 1:2:1. d. that includes a -SH group. e. in which carbon, hydrogen, and oxygen are present in a 2:1:2 ratio.
3
Name: ________________________
____
24. After 3-PGA is phosphorylated, it is reduced by a. NADP+. b. ADP. c. ATP. d. NADPH. e. CO2.
____
25. In a hypotonic solution an animal cell will a. lyse. b. lose water. c. neither gain nor lose water. d. shrivel. e. experience turgor.
____
26. Where is calcium stored? a. mitochondria b. microtubules c. centrioles d. rough endoplasmic reticulum e. smooth endoplasmic reticulum
____
27. What kind of effect does R-dopa have on Parkinson's disease? a. At first it alleviates the symptoms but over the long term it makes the symptoms worse. b. It makes the symptoms worse. c. At first it makes the symptoms worse but over the long term it alleviates the symptoms. d. It alleviates the symptoms. e. R-dopa has no effect on Parkinson's disease.
____
28. In fermentation, ____ is ____ a. NADH; oxidized b. pyruvate; oxidized c. NADH; reduced d. ethanol; oxidized e. NAD+; oxidized
____
29. ____ are surface appendages that allow a bacterium to stick to a surface. a. Pili b. Mitochondria c. Cell walls d. Flagella e. Ribosomes
____
30. What name is given to the bond between water molecules? a. polar covalent b. hydrogen c. nonpolar covalent d. ionic e. hydrophobic
____
31. In salt, what is the nature of the bond between sodium and chlorine? a. hydrogen b. ionic c. polar covalent d. nonpolar covalent e. hydrophobic
4
Name: ________________________
____
32. How many ATP molecules are produced by glycolysis? a. 1 b. 3 c. 2 d. 4 e. 5
____
33. What is the fate of the phosphate group that is removed when ATP is converted to ADP? a. It is acquired by a reactant in a spontaneous reaction. b. It is used to convert an ATP into an AQP. c. It is broken down into one phosphorus and four oxygen atoms. d. It is acquired by a reactant in an endergonic reaction. e. It is acquired by a reactant in an exergonic reaction.
____
34. Which of these functional groups does not contain oxygen? a. carboxyl b. carbonyl c. phosphate d. hydroxyl e. sulfhydryl
____
35. Water's surface tension and heat storage capacity is accounted for by its a. mass. b. weight. c. orbitals. d. size. e. hydrogen bonds.
____
36. If this functional group is at the end of a carbon skeleton, the molecule is called an aldehyde. a. carbonyl b. hydroxyl c. carboxyl d. sulfhydryl e. amino
____
37. What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule? a. hydrolysis b. anabolism c. entropic d. dehydration decomposition e. dehydration synthesis
____
38. In your body, what process converts the chemical energy found in glucose into the chemical energy found in
____
ATP? a. digestion b. redox c. cellular respiration d. potentiation e. anabolism 39. Structural isomers are molecules that a. are enantiomers. b. have a ring structure. c. are hydrocarbons. d. differ in the covalent arrangements of their atoms. e. are mirror images. 5
Name: ________________________
____
40. Most of the energy that enters electron transport enters as a. FADH2 and NADH. b. acetyl CoA. c. glucose. d. ATP. e. CO2.
____
41. What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons? a. 8 b. 18 c. +1 d. 12 e. 6
____
42. An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many electrons does
____
____
____
boron have? a. 0 b. 11 c. 15 d. 5 e. 2 43. Cholesterol enters cells via a. exocytosis. b. phagocytosis. c. osmosis. d. receptor-mediated endocytosis. e. pinocytosis. 44. In a neutral solution the concentration of a. hydrogen ions is equal to the concentration of hydroxide ions. b. water molecules is less than the concentration of hydroxide ions. c. hydrogen ions is less than the concentration of hydroxide ions. d. water molecules is less than the concentration of hydrogen ions. e. hydrogen ions is greater than the concentration of hydroxide ions. 45. Oxygen crosses a plasma membrane by a. passive transport. b. active transport. c. pinocytosis. d. phagocytosis. e. osmosis. .
____
46. The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is a. the flow of electrons down the electron transport chain. b. the H+ concentration gradient across the inner mitochondrial membrane. c. the transfer of phosphate to ADP. d. the affinity of oxygen for electrons. e. the oxidation of glucose and other organic compounds.
6
Name: ________________________
____
47. Which of the following statements is a correct distinction between autotrophs and heterotrophs? a. Autotrophs, but not heterotrophs, can nourish themselves beginning with CO 2 and other
nutrients that are inorganic. Cellular respiration is unique to heterotrophs. Only heterotrophs require chemical compounds from the environment. Only heterotrophs have mitochondria. Only heterotrophs require oxygen. 48. Choose the pair of terms that correctly completes this sentence: Nucleotides are to ____ as ____ are to proteins. a. polymers; polypeptides b. nucleic acids; amino acids c. genes; enzymes d. amino acids; polypeptides e. glycosidic linkages; polypeptide linkages 49. Which functional group is most likely to be responsible for an organic molecule behaving as a base? a. phosphate b. hydroxyl c. amino d. carboxyl e. carbonyl 50. Given what you know about the electronegativity of oxygen, predict which of the molecules shown in the figure below would be the stronger acid. b. c. d. e.
____
____
____
Molecule B Molecule A 51. Which of the following is not a protein? a. an enzyme b. an antibody c. insulin d. cholesterol e. hemoglobin 52. The structural level of a protein least affected by a disruption in hydrogen bonding is the a. primary level. b. All structural levels are equally affected. c. secondary level. d. tertiary level. e. quaternary level. 53. Which of the following processes includes all others? a. osmosis b. facilitated diffusion c. diffusion of a solute across a membrane d. transport of an ion down its electrochemical gradient e. passive transport a. b.
____
____
____
7
Name: ________________________
____
54. Most CO2 from catabolism is released during a. the citric acid cycle. b. electron transport. c. lactate fermentation. d. oxidative phosphorylation. e. glycolysis.
____
55. According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly a. randomly oriented in the membrane, with no fixed inside-outside polarity. b. embedded in a lipid bilayer. c. free to depart from the fluid membrane and dissolve in the surrounding solution. d. confined to the hydrophobic core of the membrane. e. spread in a continuous layer over the inner and outer surfaces of the membrane.
____
56. Identify the asymmetric carbon in the molecule shown in the figure below.
Carbon E Carbon A Carbon B Carbon C Carbon D 57. If an enzyme solution is saturated with substrate, the most effective way to obtain an even faster yield of products is to a. add more substrate. b. add an allosteric inhibitor. c. add more of the enzyme. d. heat the solution to 90°C. e. add a noncompetitive inhibitor. 58. What is the reducing agent in the following reaction? a. b. c. d. e.
____
____
Pyruvate + NADH + H+ Lactate + NAD+ a. b. c. d. e.
pyruvate lactate oxygen NADH NAD+
8
Name: ________________________
____
59. Which of the following metabolic processes can occur without a net influx of energy from some other
____
process? a. C6H12O6 + 6 O2 6 CO2 + 6 H2O b. amino acids protein c. glucose + fructose sucrose d. ADP + Pi ATP + H2O e. 6 CO2 + 6 H2O C6H12O6 + 6 O2 60. Which functional group is not present in the molecule shown in the figure below?
sulfhydryl amino carboxyl hydroxyl Which metabolic pathway is common to both fermentation and cellular respiration? a. synthesis of acetyl CoA from pyruvate b. reduction of pyruvate to lactate c. the electron transport chain d. glycolysis e. the citric acid cycle Some bacteria are metabolically active in hot springs because a. their enzymes are insensitive to temperature. b. they use molecules other than proteins as their main catalysts. c. high temperatures make catalysis unnecessary. d. they are able to maintain a cooler internal temperature. e. their enzymes have high optimal temperatures. In mechanism, photophosphorylation is most similar to a. substrate-level phosphorylation in glycolysis. b. the Calvin cycle. c. carbon fixation. d. oxidative phosphorylation in cellular respiration. e. reduction of NADP+. Which of the following hydrocarbons has a double bond in its carbon skeleton? a. C2H6 b. C2H2 c. C3H8 d. CH4 e. C2H4 a. b. c. d.
____
61.
____
62.
____
63.
____
64.
9
Name: ________________________
____
65. Choose the pair of terms that correctly completes this sentence: Hydroxyl is to ____ as ____ is to aldehyde. a. amine; carboxyl b. oxygen; carbon c. carbonyl; ketone d. alcohol; carbonyl e. alcohol; ketone
____
66. The molecular formula for glucose is C6H12O6. What would be the molecular formula for a polymer made by
____
____
____
linking ten glucose molecules together by dehydration reactions? a. C60H120O60 b. C60H102O51 c. C60H111O51 d. C60H100O50 e. C60H12O6 67. Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that join nucleotides together. What would happen to DNA molecules treated with these enzymes? a. The two strands of the double helix would separate. b. All bases would be separated from the deoxyribose sugars. c. The phosphodiester bonds between deoxyribose sugars would be broken. d. The purines would be separated from the deoxyribose sugars. e. The pyrimidines would be separated from the deoxyribose sugars. 68. Most cells cannot harness heat to perform work because a. heat is not a form of energy. b. temperature is usually uniform throughout a cell. c. cells do not have much heat; they are relatively cool. d. heat can never be used to do work. e. heat denatures enzymes. 69. In the following branched metabolic pathway, a dotted arrow with a minus sign symbolizes inhibition of a metabolic step by an end product:
Which reaction would prevail if both Q and S were present in the cell in high concentrations? a. O P b. M O c. L N d. R S e. L M
10
Name: ________________________
____
70. Which of the following sequences correctly represents the flow of electrons during photosynthesis? a. NADPH chlorophyll Calvin cycle b. NADPH O2 CO2
B H2O NADPH Calvin cycle H2O photosystem I photosystem II NADPH electron transport chain O2 Cells do not catabolize carbon dioxide because a. CO2 is already completely reduced. b. CO2 is already completely oxidized. c. its double bonds are too stable to be broken. d. CO2 has fewer bonding electrons than other organic compounds. e. the molecule has too few atoms. According to the first law of thermodynamics, a. all processes increase the order of the universe. b. systems rich in energy are intrinsically stable. c. energy is conserved in all processes. d. the universe constantly loses energy because of friction. e. matter can be neither created nor destroyed. Which term includes all others in the list? a. monosaccharide b. starch c. disaccharide d. polysaccharide e. carbohydrate Organic chemistry is currently defined as a. the study of hydrocarbons. b. the study of natural (as opposed to synthetic) compounds. c. the study of carbon compounds. d. the study of vital forces. e. the study of compounds that can be made only by living cells. If an enzyme has been inhibited noncompetitively, a. the active site will be occupied by the inhibitor molecule. b. raising substrate concentration will increase the inhibition. c. the inhibitor molecule may be chemically unrelated to the substrate. d. more energy will be necessary to initiate the reaction. e. the G for the reaction it catalyzes will always be negative. Which of the following does not occur during the Calvin cycle? a. consumption of ATP b. regeneration of the CO2 acceptor c. carbon fixation d. oxidation of NADPH e. release of oxygen The final electron acceptor of the electron transport chain that functions in oxidative phosphorylation is a. ADP. b. oxygen. c. NAD+. d. pyruvate. e. water. c. d.
____
71.
____
72.
____
73.
____
74.
____
75.
____
76.
____
77.
11
Name: ________________________
____
78. If an enzyme is added to a solution where its substrates and products are in equilibrium, what would occur? a. The reaction would change from endergonic to exergonic. b. Additional product would be formed. c. Additional substrate would be formed. d. Nothing; the reaction would stay at equilibrium. e. The free energy of the system would change.
____
79. Which of the following statements is a correct distinction between cyclic and noncyclic electron flow? a. Chemiosmosis is unique to noncyclic electron flow. b. In addition to ATP, cyclic electron flow also produces O 2 and NADPH. c. Only cyclic electron flow utilizes light at 700 nm. d. Only noncyclic electron flow produces ATP. e. Only cyclic electron flow can operate in the absence of photosystem II.
____
80. In what way do the various membranes of a eukaryotic cell differ? a. Only certain membranes of the cell are selectively permeable. b. Certain proteins are unique to each membrane. c. Phospholipids are found only in certain membranes. d. Only certain membranes are constructed from amphipathic molecules. e. Some membranes have hydrophobic surfaces exposed to the cytoplasm, while others
____
81.
____
82.
____
83.
____
84.
have hydrophilic surfaces facing the cytoplasm. The gasoline consumed by an automobile is a fossil fuel consisting mostly of a. alcohols. b. amino acids. c. hydrocarbons. d. aldehydes. e. thiols. When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs? a. ATP synthase pumps protons by active transport. b. The electrons gain free energy. c. NAD+ is oxidized. d. The pH of the matrix increases. e. The cytochromes phosphorylate ADP to form ATP. In what respect are the photosynthetic adaptations of C 4 plants and CAM plants similar? a. Neither C4 plants nor CAM plants have thylakoids. b. Both types of plants make sugar without the Calvin cycle. c. In both cases, an enzyme other than rubisco carries out the first step in carbon fixation. d. In both cases, only photosystem I is used. e. Both types of plants make most of their sugar in the dark. Which of the following is a true distinction between fermentation and cellular respiration? a. Substrate-level phosphorylation is unique to fermentation. b. NADH is oxidized by the electron transport chain in respiration only. c. Only respiration oxidizes glucose. d. Fermentation, but not respiration, is an example of a catabolic pathway. e. NAD+ functions as an oxidizing agent only in respiration.
12
Name: ________________________
____
____
85. In the presence of a metabolic poison that specifically and completely inhibits all function of mitochondrial
ATP synthase, which of the following would you expect? a. a decrease in the pH difference across the inner mitochondrial membrane b. an accumulation of NAD+ c. an increase in the pH difference across the inner mitochondrial membrane d. increased oxygen consumption e. increased synthesis of ATP 86. Choose the term that correctly describes the relationship between the two sugar molecules shown in the figure below.
geometric isomers isotopes structural isomers enantiomers Which of the following statements concerning unsaturated fats is true? a. They contain more hydrogen than saturated fats having the same number of carbon atoms. b. They generally solidify at room temperature. c. They have double bonds in the carbon chains of their fatty acids. d. They are more common in animals than in plants. e. They have fewer fatty acid molecules per fat molecule. In mitochondria, exergonic redox reactions a. are the source of energy driving prokaryotic ATP synthesis. b. provide the energy to establish the proton gradient. c. reduce carbon atoms to carbon dioxide. d. are coupled via phosphorylated intermediates to endergonic processes. e. are directly coupled to substrate-level phosphorylation. The light reactions of photosynthesis supply the Calvin cycle with a. sugar and O2. b. H2O and NADPH. c. ATP and NADPH. d. CO2 and ATP. e. light energy. Which of the following conclusions does not follow from studying the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis? a. Chlorophyll a has two absorption peaks. b. Chlorophyll owes its color to the absorption of green light. c. There must be accessory pigments that broaden the spectrum of light that contributes to photosynthesis. d. Not all wavelengths are equally effective for photosynthesis. e. The red and blue areas of the spectrum are most effective in driving photosynthesis. a. b. c. d.
____
87.
____
88.
____
89.
____
90.
13
Name: ________________________
____
91. Which of the following statements about the 5' end of a polynucleotide strand is correct? a. The 5' end is the fifth position on one of the nitrogenous bases. b. The 5' end has a phosphate group. c. The 5' end is identical to the 3' end. d. The 5' end has a hydroxyl group. e. The 5' end is antiparallel to the 3' end.
____
92. Which action could produce a carbonyl group? a. the addition of a thiol to a hydroxyl b. the addition of a hydroxyl to a phosphate c. the addition of a sulfhydryl to a carboxyl d. the replacement of the nitrogen of an amine with oxygen e. the replacement of the hydroxyl of a carboxyl group with hydrogen
____
93. Cooperation of the two photosystems is required for a. reduction of NADP+. b. ATP synthesis. c. generation of a proton-motive force. d. oxidation of the reaction center of photosystem I. e. cyclic photophosphorylation.
____
94. Choose the pair of terms that correctly completes this sentence:
____
____
____
Catabolism is to anabolism as ____ is to ____. a. free energy; entropy b. work; energy c. exergonic; endergonic d. entropy; enthalpy e. exergonic; spontaneous 95. Which of the following characteristics is not associated with allosteric regulation of an enzyme's activity? a. Regulatory molecules bind to a site remote from the active site. b. Inhibitors and activators may compete with one another. c. A mimic of the substrate competes for the active site. d. The enzyme usually has a quaternary structure. e. A naturally occurring molecule stabilizes a catalytically active conformation. 96. Based on the model of sucrose uptake in Figure 7.19 (in the text), which of the following experimental treatments would increase the rate of sucrose transport into the cell? a. decreasing extracellular sucrose concentration b. adding a substance that makes the membrane more permeable to hydrogen ions c. decreasing extracellular pH d. decreasing cytoplasmic pH e. adding an inhibitor that blocks the regeneration of ATP 97. Which of the following factors would tend to increase membrane fluidity? a. a relatively high protein content in the membrane b. a greater proportion of relatively large glycolipids compared to lipids having smaller molecular masses c. a greater proportion of unsaturated phospholipids d. a greater proportion of saturated phospholipids e. a lower temperature
14
Name: ________________________
____
98. Which of the following processes is most directly driven by light energy? a. creation of a pH gradient by pumping protons across the thylakoid membrane b. removal of electrons from chlorophyll molecules c. carbon fixation in the stroma d. reduction of NADP+ molecules e. ATP synthesis
____
99. Which of the following pairs of base sequences could form a short stretch of a normal double helix of DNA? a. 5'-purine-pyrimidine-purine-pyrimidine-3' with b. c. d. e.
3'-purine-pyrimidine-purine-pyrimidine-5' 5'-A-G-C-T-3' with 5'-T-C-G-A-3' 5'-G-C-G-C-3' with 5'-T-A-T-A-3' 5'-A-T-G-C-3' with 5'-G-C-A-T-3' A, B, and D are all correct.
. 100. The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are the
form. Which of the following could amylase break down? (Choose all that apply) A) B) C) D) E)
cellulose chitin glycogen starch amylopectin
15
