Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
Part I: Short answers
1. Membrane proteins have a variety of functions. State four membrane protein functions.
A. ______________________________________________________________________________________
B. ______________________________________________________________________________________
C. ______________________________________________________________________________________
D. ______________________________________________________________________________________
Part II: Label the components
2. Label the components of a biological membrane illustrated below: Each of the following answers can only be
used once.
Transmembrane protein Single pass protein
Phospholipids
Carbohydrates
Cholesterol
A. ________________________________________
B. ________________________________________
C. ________________________________________
D. ________________________________________
E. ________________________________________
Part III: Fill in the Blanks
3. ______________________________ At high concentrations of substrate, the rate of enzyme catalyzed
reactions may plateau. This is called _____________________.
4. ______________________________ The final electron acceptor in aerobic respiration is __________.
5. ______________________________ Proteins that carry out catalysis in organisms are called _______.
6. ______________________________ The first intermediate product of the Kreb’s cycle is __________.
7. ______________________________ The process whereby early steps in a complex metabolic pathway
are inhibited by the end products of the pathway is referred to as
______________________.
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Biol 178
Exam 2 Study Guide & Practice Exam
Part IV: Multiple Choice
8.Which of the following uses clathrin?
(A) The sodium-potassium pump
(B) The sodium-glucose symport
(D) Receptor mediated endocytosis
(E) ATP hydrolysis
Fall 2006
(C) Osmosis
9.Which of the following involves transport of substances up a concentration gradient?
(A) Sodium-potassium pump
(B) Osmosis
(C) Facilitated diffusion
(D) simple diffusion
(E) All of the above
10. The ATP generated during glycolysis, is produced via
A. chemiosmosis
B. substrate-level phosphorylation
D. oxidative phosphorylation
E. ATP synthase
C. electron transport
11. Many hormones induce changes in cells by first binding to plasma membrane
A) marker proteins
B) pores C) rough ER
D) channels
E) surface receptors
12. The plasma membrane is a thin sheet of lipid embedded with large embedded molecules called
A) proteins
B) carbohydrates C) nucleotides
E) sodium and potassium ions
13. If a cell has the same concentration of dissolved molecules as of its outside environment, the external solution is
__________________ relative to the cell.
A) isotonic/isosmotic
B) hypertonic C) hypotonic
14. A type of transport of a solute across a membrane from a low to a high concentration is known as
A) osmosis
B) diffusion
C) facilitated transport
D) active transport
E) exocytosis
15. In the diagram below, which of the blood cells would be expected after being placed in a hypertonic solution?
A. A
B. B
C. C
16. Some proteins of the plasma membrane extend across the entire width of the membrane only once. These have been
known to function as
A) pores
B) channels
C) cell surface receptors
D) A & B
17. On the outer surface of the plasma membrane there are marker molecules that identify the cell-type. Often these
molecules are
A) ATP
B) amino acids
C) nucleotides
D) carbohydrate chains
E) inorganic ions
18. The illustration below is a model of a
A. phospholipid
B. protein
C. cholesterol
19. Cholesterol functions in the plasma membrane to
A) transport ions B) serve as an energy molecule
C) add rigidity D) mediate steroid action
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D. nucleic acid
Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
20. The Fluid Mosaic Model states that
A) The cell membrane was composed of lipids and proteins.
B) The cell membrane was composed of a phospholipid bilayer between two layers of globular proteins.
C) The cell membrane was composed of a phospholipid bilayer with proteins inserted into the bilayer.
D) The cell membrane was composed only of a phospholipid bilayer.
21. For the process of diffusion to occur, molecules must
A) Move from areas of high concentration to areas of lesser concentration until an equilibrium is reached.
B) Move from areas of low concentration to areas of higher concentration until an equilibrium is reached.
C) Remain stationary until their molecular motion allows for an equilibrium to be reached.
D) Move from areas of high concentration to areas of lesser concentration by facilitated transport.
E) Move from areas of high concentration to areas of lesser concentration by active transport.
22. If a blood research laboratory is attempting to collect the content of human red blood cells, the researchers
should use which of the following types of solutions to cause blood cell lysis (bursting)?
A) hyperosmotic B) isosmotic
C) hypoosmotic
23. Which of the following is not a component of an animal cell membrane?
A) phospholipids B) polynucleotides
C) protein
D) glycolipids
E) cholesterol
24. Turgor pressure is a direct result of the roots of plant cells existing in a _____________ environment.
A) hypoosmotic
B) isosmotic
C) hyperosmotic
Use the following to answer questions 45-48:
Match the statement to the following options.
A. exterior
B. glycolipids
C. phospholipid bilayer
25. Fluid, hydrophobic barrier.
26. May serve as cell surface markers.
27. Channels of the sodium-potassium pump.
D. transmembrane proteins
28. Bulk transport of material from the cytoplasm to the external environment is accomplished by the process of
A. endocytosis
B. exocytosis
29. A white blood cell (called a macrophage) can destroy a bacterium by first bringing it into the cytoplasm of the cell
through a process called
A. endocytosis
B. phagocytosis
C. pinocytosis
30.The substrate fits in the ____________ of an enzyme:
(A) allosteric site
(B) active site
(C) reaction groove
(E) inhibitor site
(D) Golgi body
31.Coenzymes are:
(A) non-protein molecules that aid enzyme catalysis.
(B) protein molecules that aid enzyme catalysis.
(C) enzyme inhibitors
(E) none of the above.
32.Enzymes speed up reaction rates because:
(A) they supply the activation energy
(D) they increase the activation energy
33.When NAD+ is reduced it:
(A) gains one electron and one hydrogen.
(C) gains 2 electrons and one hydrogen.
(E) gains 2 electons and 2 hydrogens.
(B) they provide heat
(E) B and C.
(C) they lower the activation energy.
(B) loses one electron.
(D) gains 2 electrons only.
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(D) enzyme substrates.
Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
34.Photosynthesis can be broken down into 2 principle stages, which are:
(A) the light reactions and Krebs cycle.
(B) glycolysis and the Calvin cycle.
(C) electron transport in the chloroplasts and in the mitochondria.
(D) the light reactions and the Calvin cycle
(E) none of the above.
35.Plants are examples of:
(A) autotrophic organisms
(D) photosynthetic organisms
(B) heterotrophic organisms
(E) A, C, and D.
(C) photoautotrophic organisms.
36.Leaves of deciduous trees turn red, orange, and yellow in fall because:
(A) frost damages chlorophyll
(B) chlorophyll is no longer manufactured
(C) the carotenoid pigments are no longer masked
(D) carotenoids are no longer manufactured.
(E) B and C.
37.Which of the following are examples of electron carriers that are used in photosynthesis?
(A) NAD
(B) NADP+
(C) FADH2
(D) A and C
(E) All of the above.
38.Photosynthesis occurs in:
(A) leaves
(B) roots
(E) A and D
39. Chlorophylls a and b mainly absorb:
(A) violet-blue and red light
(D) orange and yellow light
(C) the cell wall
(D) mitochondria and chloroplasts
(B) green light
(C) blue and green light
(E) all of the above
40.In the light reactions of photosynthesis, high energy electrons are passed out of the photosystem by:
(A) the electron acceptor molecule
(B) the electron donor molecule
(C) carotenoids
(D) specialized chlorophyll a molecules
(E) B and D
41.In photosynthesis, ATP is made in the:
(A) matrix
(B) thylakoid space
(E) cytoplam.
(C) stroma
42.The energy for life is produced by:
(A) respiration
(B) fermentation
(E) none of the above
43.The waste products of respiration are used for:
(A) photosynthesis
(B) respiration
(E) nucleotide synthesis
(D) intermembrane space
(C) photosynthesis
(C) deforestation
(D) sex
(D) heredity
44.The H+ are pumped from _______ to _______ in the electron transport chain of photosynthesis:
(A) stroma to thylakoid space
(B) thylakoid space to stroma
(C) matrix to intermembrane space
(D) intermembrane space to matrix
(E) None of the above – H+ are not pumped, they move down their concentration gradient only
45.Grana is/are:
(A) enzymes that function in active transport
(C) stacks of thylakoids
(D) aging cells
(B) found in the chloroplasts
(E) B and C
46.The potential energy that an electron loses as it is passed down the electron transport chain to photosystem I is
used to:
(A) pump protons into the stroma
(B) pump protons into the thylakoid space
(C) pump hydrogen ions from the stroma to the thylakoid space
(D) synthesize ATP
(E) B, C, and D
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Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
47. Which of the following is not true? ATP synthase:
(A) functions in breaking down ATP into ADP and P i
(B) allows H+ to diffuse back to the stroma
(C) is found in the thylakoid membrane
(D) is an enzyme
(E) converts mechanical energy to chemical energy
48.The antenna complex is:
(A) a system of transmembrane proteins that function in electron transport.
(B) a protein that pumps hydrogen ions.
(C) a light gathering system of chlorophyll molecules and accessory pigments.
(D) a pair of chlorophyll a molecules that function as electron donors.
(E) An enzyme that reduces NADPH.
49.The end product of glycolysis is:
(A) acetyl-co A
(B) carbon dioxide and water
(E) oxaloacetate
50.The Krebs cycle occurs in the:
(A) cytoplasm
(B) stroma
(E) inner mitochondrial membrane.
(C) matrix
51. The final electron acceptor in aerobic respiration is:
(A) water
(B) oxygen
(C) NAD+
(C) pyruvate
(D) glucose
(D) thylakoid membrane
(D) FADH2
(E) glucose
52. In aerobic respiration carbon dioxide is produced in:
(A) gycolysis
(B) Krebs cycle
(C) acetyl-coA production
(D) the electron transport chain
(E) B and C
53.
The function of glycolysis is to:
(A) produce NADPH and ATP
(B) produce the starting material for further energy extraction by oxidation
(C) produce glucose
(D) produce NADH and FADH2
(E) make 36 ATP from one glucose molecule
54. The net energetic products of the Krebs cycle (per molecule of glucose) are:
(A) 2 ATP and 2 NADH
(B) 2 ATP, 6 NADH, and 2 FADH2
(C) 2 NADH
(D) 36 ATP
(E) one molecule of glucose and 9 ATP
55. 32 ATP net, rather than 34 ATP net, are theoretically made by the electron transport chain of respiration
because:
(A) the NADH made by glycolysis has to be transported into the mitochondrial matrix.
(B) the NADH made by glycolysis has to be transported into the cytoplasm.
(C) the NADH made by Krebs cycle has to be transported into the mitochondrial matrix..
(D) the NADH made by Krebs cycle has to be transported into the cytoplasm.
(E) none of the above.
56.
ATP is used to fuel:
(A) passive processes
(B) endergonic reactions
(D) movement of water across the plasma membrane
(C) diffusion
(E) all of the above
57. Which of the following is not a part of the ATP molecule?
(A) adenine
(B) ribose sugar
(C) deoxyribose sugar
(D) phosphate
(E) A and B
58. ATP is usually recycled from:
(A) DNA
(B) AMP and inorganic phosphate
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(C) ADP and inorganic phosphate
Biol 178
(D) NADH
Exam 2 Study Guide & Practice Exam
Fall 2006
(E) None of the above, it is always made directly from sugar, base, and phosphate
59. According to the 2nd law of Thermodynamics, entropy is ______________________ in the universe.
A. increasing
B. decreasing
C. remaining constant
D. fluctuating depending on the current total amount of energy
E. none of the above
60. When a molecule is reduced
A. it gains a hydrogen ion
B. it loses a hydrogen atom
C. it gains a hydrogen atom
D. it loses a hydrogen ion
E. none of the above
61. Energy is transferred in redox reactions
A. by endergonic reactions
B. by ATP
C. by electrons
D. using chemiosmotic coupling
E. through carbon atoms
62. In an endergonic reaction
A. energy must be supplied for the reaction to proceed
B. the reaction will proceed if catalyzed
C. the reactants have more energy than the products
D. the reaction will proceed spontaneously and energy will be released
E. there is no activation energy required for the reaction to proceed
63. Enzymes are
A. polysaccharides
B. nucleotides
C. Deoxyribonucleic acids
D. Fatty acids
E. Proteins
64. Catalysts
A. can make endergonic reactios proceed
B. can produce greater amounts of product than in reactions that are not catalyzed
C. can lower the activation energy required for an exergonic reaction
D. decrease the rate of a reaction
E. all of the above
65. Enzyme specificity is due to
A. the tertiary structure of the enzyme
B. the 3-dimenstional shape of the active site
C. interactions between “R” groups of the amino acids making up the enzyme
D. patterns of hydrogen bonding involved in the folding of the enzyme
E. all of the above
66. An enzyme can do which of the following in catalyzing a reaction
A. orient the reactants
B. place physical strain on the substrate to help in breaking chemical bonds
C. add charge to a substrate
D. increase the overall rate of the reaction
E. all of the above
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Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
67. ATP
A. is a non-renewable source of energy
B. carries energy in sulfate bonds
C. couples endergonic and exergonic reactions
D. is only forned in chemiosmosis
E. is a modified protein
68. In competitive inhibition
A. the substrate binds to a site other than the active site
B. the cell regulates the synthesis of one enzyme in a metabolic pathway
C. a molecule other than the substrate binds to the active site blocking the binding of the substrate
D. the enzyme is denatured
E. enzymes are produced in an inactive state
69. Metabolism can be described as
A. Maintenance of a stable environment within the body
B. The transmission of traits from generation to generation
C. The sum of chemical processes that take place in living cells
D. Synthesis of macromolecules
E. The process of gas exchange across cell membranes
70. What properties of cell membranes prevents them from dissolving in water?
A. The polar heads of the phospholipids
B. Hydrogen bonding between the phosphate group of the phopholipids and water
C. The hydrophobic hydrocarbon tails of the phospholipids
D. The double carbon bonds in the unsaturated hydrocarbon tails of the phospholipids
E. None of the above
71. All of the following are true of the chloroplast except
A. contain a green pigment called chlorophyll
B. proteins of the electron transport chain are embedded in thylakoid membranes
C. are the site of the Kreb’s cycle
D. contain their own genome
E. may be 1 to several hundred per cell
72. The type of membrane transport which requires specific carrier molecules and energy to carry molecules against
their concentration gradient is
A. osmosis
B. chemiosmosis
C. dissusion
D. facilitated diffusion
E. active transport
73. In the aerobic breakdown of glucose, how many total ATP molecules are generated from one molecule of
glucose?
A. 2
B. 12
C. 24
D. 36
E. 40
74. Yeast cells actively making beer produce how much energy from the breakdown of a single glucose molecule?
A. 0
B. 2
C. 12
D. 24
E. 36
75. Grana is/are
A. the inner membrane of a mitochondrion
B. found n the chloroplasts
C. stacks of thylakoids
D. organelles
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Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
E. B and C
76. Which of the following does not involve the plasma membrane?
A. receptor mediated endocytosis
B. active transport
C. phagocytosis
D. pinocytosis
E. none of the above
77. The inner mitochondrial membrane is folded to
A. provide a strong barrier to diffusion
B. increase surface area
C. decrease surface area
D. increase the number of chlorophyll molecules available for photosynthesis
E. make sure it fits within the outer membrane
78. Which of the following is an example of diffusion?
A. Movement of a protein into a cell against its concentration gradient
B. Movement of oxygen from the tissue fluid into a respiring cell
C. Movement of carbon dioxide from a respiring cell into the tissue fluid
D. A and B
E. B and C
79. Water enters the cell through ________________, which are polar channels in the membrane.
A. aquaporins
B. sodium-potassium pumps
C. ion channels
D. endocytosis
E. integrins
80. Coenzymes are
A. non-protein molecules that aid enzyme catalysis
B. protein molecules that aid enzyme catalysis
C. enzyme inhibitors
D. enzyme substrates
E. all of the above
81. Chlorophylls a and b mainly absorb
A. violet-blue and red light
B. green light
C. blue and green light
D. orange and yellow light
E. all of the above
82. In the first reaction of the Kreb’s cycle, a _____________ carbon molecule is combined with a ____________
carbon molecule to produce citrate.
A. 1, 1
B. 1, 5
C. 3, 3
D. 2, 4
E. 1, 2
83. The H+ are pumped from the __________ to the ________________ in the electron transport of chain of
photosynthesis.
A. stronma to thylakoid space
B. thylakoid space to stroma
C. matrix to intermembrane space
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Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
D. intermembrane space to matrix
E. Non of the above – protons are not pumped, they simply diffuse across the membrane
84. The potential energy that an electron loses as it is passed down the electron transport chain to photosystem I is
used to:
A. pump protons into the stroma
B. pump protons into the thylakoid space
C. pump hydrogen ions from the stroma to the thylakoid space
D. sysntesize ATP
E. B,C, and D
85. Objects that are not actually moving, but have the capacity to do so have _______________energy.
A. kinetic
B. activation
C. thermodynamic
D. redox
E. potential
86. When the rate of enzyme catalysis is plotted against temperature, the curve suddenly drops at high temperatures
because:
A. the enzymes denature
B. this is the optimal temperature for enzyme catalysis
C. the enzyme is inhibited
D. the substrates move very fast at high temperatures
E. none of the above
87. During heavy exercise, the hominid (humans) experience muscle fatigue as the result of
A. alcohol fermentation
B. aerobic respiration
C. the build up of lactic acid
D. to much NAD+ being present in the cell
E. electron transport working too heavily
88. Transmembrane proteins are held in the plama membrane
A. by hydrophilic interactions
B. by connections to phospholipids
C. by connections to cholesterol
D. by hydrophobic interactions
E. proteins are not held in the plasma membrane and are free to leave the membrane at will
89. Which of the following does not occur during glycolysis?
A. sugar splitting
B. carbon dioxide release
C. NADH production
D. ATP production
E. Glucose priming
90. During which stage of glucose breakdown is the most ATP generated?
A. glycolysis
B. pyruvate oxidation
C. Krebs cycle
D. Calvin cycle
E. electron transport chain
91. Which of the following effects on cellular respiration would not be true if the outer mitochondrial wall was
punctured?
A. ATP synthesis powered by the electron transport chain would not occur
B. The proton gradient across the inner mitochondrial membrane would be abolished
C. Glycolysis would still continue
D. NADH and FADH2 could still donate electrons to the electron transport chain
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Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
E. ATP synthase would still maintain its function
92. In plants, photosystems absorb ____________, which are used to push electrons to a higher energy level.
A. heat
B. electrons
C. chlorophyll
D. photons
E. ATP
93. The hydrocarbon tail of a chlorophyll molecule
A. anchors it in the thylakoid membrane
B. pumps hydrogen ions across the membrane
C. excites an electron to a higher energy level when a photon is absorbed
D. absorbs red wavelengths of light
E. passes an electron to the reaction center
94. Photophosphorylation
A. occurs in the chloroplast
B. occurs in the mitochondria
C. involves electron transport
D. is a specific type of chemiosmosis
E. all are correct except B
95. All of the following are accessory pigments in photosynthesis except
A. carotenoids
B. phycobilins
C. chlorophyll a
D. chlorophyll b
E. All of these are accessory pigments
Figure 1: Redox reaction
96. (Figure 1) Which molecule has been oxidized?
A. A0
B. B0
C. A+
D. BE. Electrons
97. (Figure 1) Which molecule has been reduced?
A. A0
B. B0
C. A+
D. BE. Electrons
98. (Figure 1) Which molecule has the greatest potential energy?
A. A0
B. B0
C. A+
D. BE. Electrons
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Biol 178
Exam 2 Study Guide & Practice Exam
Fall 2006
Figure 2: Model of Transport across a cell membrane.
99. (Figure 2) Which substances are being transported actively?
A. K+
B. Na+
C. sugar D. A & B
E. A, B & C
100. (see Figure 2) The type of transport observed with sugar going into the cell together with sodium ions is an
example of
A) active transport
B) Cotransport
C. passive transport
D. A & B
Part IV: Visuals
You should be able to correctly identify all of the monomers from Part II of the last exam as well as be able to
identify any or all of the following structures: Phospholipid, NADH, mitochondria, ATP, chloroplast, chlorophyll
molecule, ATP synthase
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