6. In human muscle cells, the fermentation process produces
A) lactic acid.
B) 12 moles of ATP.
C) pyruvic acid.
D) an excessive amount of energy.
E) None of the above
7. Most ATP produced in our bodies is made
A) by glycolysis.
B) in the citric acid cycle.
C) using ATP synthase.
D) from photosynthesis.
E) by burning fat.
8. ATP is
A) a short-term energy-storage compound.
B) the cell's principal compound for energy transfers.
C) synthesized within mitochondria.
D) the molecule all living cells rely on to do work.
E) All of the above
9. According to the chemiosmotic theory, the energy for the synthesis of ATP during the
flow of electrons down the respiratory chain is provided directly by the
A) hydrolysis of GTP.
B) reduction of NAD
+
.
C) diffusion of protons.
D) reduction of FAD.
E) hydrolysis of ATP.
10. When NADH donates two electrons to ubi
quinone during respiration, ubiquinone is
A) reduced.
B) oxidized.
C) phosphorylated.
D) aerobic.
E) hydrolyzed.
Page 2
11. Which process converts glucose to pyruvate, generating a small amount of ATP but no
carbon dioxide?
A) Pyruvate oxidation
B) Glycolysis
C) The citric acid cycle
D) Respiratory chain
E) Gluconeogenesis
12. During the citric acid cycle, energy stored in acetyl CoA is used to
A) create a proton gradient.
B) drive the reaction ADP + P
i
→
ATP.
C) reduce NAD
+
to NADH.
D) drive the reaction oxaloacetate
→
citric acid.
E) reduce FAD to FADH
2
.
13. The function of NAD
+
is to
A) cause the release of energy to adjacent cells when energy is needed in aerobic
conditions.
B) hasten the release of energy when the cell has been deprived of oxygen.
C) carry hydrogen atoms and free energy from compounds being oxidized and to give
hydrogen atoms and free energy to compounds being reduced.
D) block the release of energy to adjacent cells.
E) None of the above
14. Which of the following oxidizes other compounds by gaining free energy and hydrogen
atoms and reduces other compounds by giving up free energy and hydrogen atoms?
A) Vitamins
B) Adenine
C) ATP
D) NAD
E) Riboflavin
15. The electron transport chain contains four large protein complexes (I, II, III, and IV),
cytochrome c, and ubiquinone. The function of these molecules is to
A) transport electrons.
B) ensure the production of water and oxygen.
C) regulate the passage of water through the chain.
D) oxidize NADH.
E) None of the above
Page 3
16. For the citric acid cycle to proceed, it is necessary for
A) pyruvate to bind to oxaloacetate.
B) carbon dioxide to bind to oxaloacetate.
C) an acetyl group to bind to oxaloacetate.
D) water to be oxidized.
E) None of the above
17. Some of the free energy released by oxidation of pyruvate to acetate is stored in acetyl
CoA. How does acetyl CoA store free energy?
A) Acetyl CoA has a higher free energy than acetate.
B) Acetyl CoA is an electron carrier.
C) Acetyl CoA is a phosphate donor.
D) Acetate + CoA
→
acetyl CoA is an exergonic reaction.
E) Reduction of acetyl CoA is coupled to ATP synthesis.
18. In the first reaction of glycolysis, glucose receives a phosphate group from ATP. This
reaction is
A) respiration.
B) a redox reaction.
C) exergonic.
D) endergonic.
E) fermentation.
19. When hydrogen ions are pumped from the mitochondrial matrix across the inner
membrane into the intermembraneous space, the result is the
A) formation of ATP.
B) reduction of NAD
+
.
C) creation of a proton gradient.
D) restoration of the Na
+
-K
+
balance across the membrane.
E) reduction of glucose to lactic acid.
20. When a cell needs energy, cellular respiration is regulated by isocitrate dehydrogenase,
an enzyme of the citric acid cycle. This enzyme is stimulated by
A) H
+
.
B) heat.
C) oxygen.
D) ADP.
E) None of the above
Page 4
21. The oxidizing agent at the end of the electron transport chain is
A) O
2
.
B) NAD
+
.
C) ATP.
D) FAD.
E) ubiquinone.
22. The formation of ethanol from pyruvate is an example of
A) an exergonic reaction.
B) an extra source of energy as the result of glycolysis.
C) a fermentation process that takes place in the absence of oxygen.
D) cellular respiration.
E) None of the above
23. Which of the following scientific tools “cracked” the Calvin–Benson cycle?
A) Isotopes
B) Paper chromatography
C) Crystallography
D) Centrifugation and electron microscopy
E) Both a and b
24. The energy source for the synthesis of carbohydrates in the Calvin cycle is
A) ATP only.
B) photons.
C) energized chlorophyll
a
.
D) NADPH + H
+
.
E) NADPH + H
+
and ATP.
25. When RuBP reacts with O
2
,
A) it cannot react with CO
2
.
B) carbohydrate production increases.
C) plant growth is stimulated.
D) net carbon fixation increases by 25 percent.
E) two carbon molecules combine to form the four-carbon phosphoglycolate.
26. The NADPH required for the reduction of 3PG to G3P comes from
A) the dark reactions.
B) the light reactions.
C) the synthesis of ATP.
D) the Calvin cycle.
E) oxidative phosphorylation.
Page 5
27. How do red and blue light differ from one another?
A) They differ in intensity.
B) They have a different number of photons in each quantum.
C) Their wavelengths are different.
D) They differ in duration.
E) Red is radiant, whereas blue is electromagnetic.
28. A suspension of algae is incubated in a flask in the presence of both light and CO
2
.
When it is transferred to the dark, the reduction of 3-phosphoglycerate to
glyceraldehyde 3-phosphate is blocked and th
e concentration of ribulose bisphosphate
(RuBP) declines. Why does the RuBP concentration decline?
A) Ribulose bisphosphate is synthesi
zed from glyceraldehyde 3-phosphate.
B) Glyceraldehyde 3-phosphate is converted to glucose.
C) Ribulose bisphosphate is used to synthesize 3-phosphoglycerate.
D) Both a and b
E) Both a and c
29. Free energy is released in cyclic photophosphorylation
A) by the formation of ATP.
B) during the excitation of chlorophyll.
C) during the fluorescence of chlorophyll.
D) during each of the redox reactions of the electron transport chain.
E) when electrons are transferred from photosystem I to photosystem II.
30. The enzyme rubisco is found in
A) chloroplasts.
B) mitochondria.
C) the cytoplasm.
D) the nucleus.
E) yeast.
31. When white light strikes a blue pigment, blue light is
A) reduced.
B) absorbed.
C) converted to chemical energy.
D) scattered or transmitted.
E) used to synthesize ATP.
Page 6
32. The level of atmospheric CO
2
has varied considerably over the years. Currently, the
level of atmospheric CO
2
A) is four times what is was during the time of the dinosaurs.
B) favors C
4
plants.
C) has resulted in maximum CO
2
fixation by rubisco.
D) is decreasing.
E) prevents the occurrence of photorespiration.
33. The precise moment when light energy is captured in chemical energy is the point at
which
A) light shines on chlorophyll.
B) water is hydrolyzed.
C) chlorophyll is oxidized.
D) chlorophyll is reduced.
E) the CO
2
from air is captured in a sugar.
34. In C
4
plants, starch grains are found in the chloroplasts of
A) the thylakoids.
B) mesophyll cells.
C) the intracellular space.
D) the stroma.
E) bundle sheath cells.
35. Plants are green because
A) chlorophylls absorb blue and orange-red wavelengths of light and reflect green
light.
B) chloroplasts transmit green light.
C) energized chlorophyll
a
emits green light.
D) plants possess green pigment.
E) chlorophylls absorb green light.
36. During CO
2
fixation, CO
2
combines with
A) NADPH.
B) 3PG.
C) G3P.
D) water.
E) 1,5-ribulose bisphosphate.
Page 7
37. In C
4
plants, the function of the four-carbon compound that is synthesized in the
mesophyll cells is to
A) reduce NADP
+
.
B) combine with CO
2
to produce glucose.
C) carry CO
2
to the bundle sheath cells.
D) drive the synthesis of ATP.
E) close the stomata.
38. The photosynthetic pigment chlorophyll a absorbs
A) infrared light.
B) orange-red and blue light.
C) X rays.
D) gamma rays.
E) white light.
Use the following to answer question 39:
Refer to the diagram below to answer the following question.
Page 8
39.
Diagram
- The Ruben and Kamen experiments tracing isotopes of oxygen through the
process of photosynthesis proved that
A) all the oxygen gas produced during photosynthesis comes from water.
B) CO
2
is the source of oxygen released during photosynthesis.
C) the oxygen released by water is incorporated into glucose.
D) oxygen is needed to made rubisco.
E) NADPH is made during the Calvin cycle.
40. In C
4
plants, CO
2
is first fixed into a compound called
A) pyruvate.
B) glucose.
C) oxaloacetate.
D) ribulose bisphosphate.
E) 3-phosphoglycerate.
41. When a photon is absorbed by a molecule, the photon
A) loses its ability to generate any energy.
B) raises the molecule from a ground state of low energy to an excited state.
C) affects the molecule in ways that are not clearly understood.
D) causes a change in the velocity of the wavelengths.
E) None of the above
42. Photorespiration reduces the net carbon fixed by the Calvin cycle by _______ percent.
A) 70
B) 25
C) 2.1
D) 0.21
E) 0.02
43. When a photon interacts with molecules such as those within chloroplasts, the photons
may
A) bounce off the molecules, having no effect.
B) pass through the molecules, having no effect.
C) be absorbed by the molecules.
D) Both a and c
E) All of the above
Page 9
44. The Calvin–Benson cycle uses more ATP than NADPH + H
+
. The needed ATP comes
from
A) the splitting of water.
B) the reduction of oxygen.
C) the oxidation of glucose.
D) cyclic P
700
.
E) noncyclic electronic transport.
45. In noncyclic photophosphorylation, the chlorophyll in photosystem I is reduced by
A) water.
B) an electron from the transport chain of photosystem II.
C) two photons of light.
D) NADPH.
E) ATP.
46. Which of the following is the revised, balanced equation for the generation of sugar
from sunlight, water, and CO
2
?
A) 6 CO
2
+ 6 H
2
O
→
C
6
H
12
O
6
+ O
2
B) 6 CO
2
+ 12 H
2
O
→
C
6
H
12
O
6
+ 6 O
2
+ 6 H
2
O
C) 6 CO
2
+ 6 H
2
O
→
C
6
H
12
O
6
+ 6 O
2
D) 12 CO
2
+ 12 H
2
O
→
2 C
6
H
12
O
6
+ 2 O
2
E) None of the above
47. The energy to hydrolyze water comes from
A) oxidized chlorophyll.
B) reduced chlorophyll.
C) the proton gradient.
D) ATP.
E) NADPH + H
+
.
48. Photosynthesis and respiration are linked through the
A) Calvin cycle.
B) citric acid cycle.
C) enzyme rubisco.
D) need for light.
E) a, b, and c
Page 10
49. The energy difference between an electron excited by a photon and the electron in its
ground state is _______ of the photon.
A) less than the energy
B) greater than the energy
C) equal to the energy
D) related to the wavelength
E) Both c and d
50. When a suspension of algae is incubated in a flask in the presence of light and CO
2
and
then transferred to the dark, the reduction of 3-phosphoglycerate to glyceraldehyde 3-
phosphate is blocked. This reaction stops when the algae are placed in the dark because
A) the reaction requires CO
2
.
B) the reaction is exergonic.
C) the reaction requires ATP and NADPH + H
+
.
D) the reaction requires O
2
.
E) chlorophyll is not synthesized in the dark.
51. When a photon is absorbed by chlorophyll,
A) the chlorophyll becomes “excited,” or energized.
B) a greater number of light wavelengths can be absorbed.
C) ATP is split into ADP, phosphate, and energy.
D) hydrogen ions are released.
E) the chlorophyll molecules fluoresce.
52. How many moles of CO
2
must enter the Calvin–Benson cycle for the synthesis of one
mole of glucose?
A) 1
B) 2
C) 3
D) 6
E) 12
53. In the absence of oxygen, cells capable of fermentation
A) accumulate glucose.
B) no longer produce ATP.
C) accumulate pyruvate.
D) oxidize FAD.
E) oxidize NADH to produce NAD
+
.
Page 11
54. During glycolysis, for each mole of glucose oxidized to pyruvate,
A) 6 moles of ATP are produced.
B) 2 moles of ATP are produced.
C) 4 moles of ATP are produced.
D) 2 moles of NAD
+
are produced.
E) no ATP is produced.
55. Yeast cells tend to create anaerobic conditions because they use oxygen more quickly
than it can be replaced by diffusion through the cell membrane. For this reason, yeast
cells
A) exhibit a red pigment.
B) exhibit a green pigment.
C) die.
D) produce ethanol.
E) None of the above
56. In steps 6 through 10 of glycolysis, the conve
rsion of one molecule of glyceraldehyde 3-
phosphate to pyruvate yields 2 molecules of ATP. But the oxidation of glucose to
pyruvate produces a total of 4 molecules of ATP. Where do the remaining 2 molecules
of ATP come from?
A) One mole of glucose yields 2 molecules of glyceraldehyde 3-phosphate.
B) Two molecules of ATP are used during th
e conversion of glucose to glyceraldehyde
3-phosphate.
C) Glycolysis produces 2 molecules of NADH.
D) Fermentation of pyruvate to lactic acid yields 2 molecules of ATP.
E) Fermentation of pyruvate to lactic acid yields 2 molecules of NAD
+
.
57. The chemiosmotic generation of ATP is driven by
A) osmotic movement of water into an area of high solute concentration.
B) the addition of protons to ADP and phosphate via enzymes.
C) oxidative phosphorylation.
D) the proton-motive force.
E) isocitrate dehydrogenase.
58. Water is a by-product of cellular respiration. The water is produced as a result of the
A) combining of carbon dioxide with protons.
B) conversion of pyruvate to acetyl CoA.
C) degradation of glucose to pyruvate.
D) reduction of oxygen at the end of the electron transport chain.
E) None of the above
Page 12
59. Electron transport within NADH-Q reductase, cyto chrome reductase, and cytochrome
oxidase can be coupled to proton transport from the mitochondrial matrix to the space
between the inner and outer mitochondrial membranes, because those protein complexes
are
A) in the mitochondrial matrix.
B) within the inner mitochondrial membrane.
C) in the space between the inner and outer mito chondrial membranes.
D) in the cytoplasm.
E) loosely attached to the inner mitochondrial membrane.
60. Substrate-level phosphorylation is the transfer of a(n)
A) phosphate to a protein.
B) phosphate to a substrate.
C) phosphate to an ADP.
D) ATP to a protein.
E) phosphate from ATP to a substrate.
Page 13
Answer Key
1. C
2. C
3. B
4. A
5. A
6. A
7. C
8. E
9. C
10. A
11. B
12. D
13. C
14. D
15. A
16. C
17. A
18. D
19. C
20. D
21. A
22. C
23. E
24. E
25. A
26. B
27. C
28. E
29. D
30. A
31. D
32. B
33. C
34. E
35. A
36. E
37. C
38. B
39. A
40. C
41. B
42. B
43. E
44. D
Page 14
45. B
46. B
47. A
48. A
49. E
50. C
51. A
52. D
53. E
54. C
55. D
56. A
57. D
58. D
59. B
60. C
Page 15
No comments:
Post a Comment