cd

15) What wavelength of light is most effective in driving photosynthesis? A) 420 mm B) 475 mm C) 575 mm D) 625 mm E) 730 mm

A

25) What does cyclic electron flow in the chloroplast produce? A) ATP B) NADPH C) glucose D) A and B E) A, B, and C

A

29) Suppose the interior of the thylakoids of isolated chloroplasts were made acidic and then transferred in the dark to a pH-8 solution. What would be likely to happen? A) The isolated chloroplasts will make ATP. B) The Calvin cycle will be activated. C) Cyclic photophosphorylation will occur. D) Only A and B will occur. E) A, B, and C will occur.

A

33) Where is the electron transport chain found in plant cells? A) thylakoid membranes of chloroplasts B) stroma of chloroplasts C) inner membrane of mitochondria D) matrix of mitochondria E) cytoplasm

A

37) reduction of NADP+ A. photosynthesis B. respiration C. both photosynthesis and respiration D. neither photosynthesis nor respiration

A

41) Where do the enzymatic reactions of the Calvin cycle take place? A) stroma of the chloroplast B) thylakoid membranes C) outer membrane of the chloroplast D) electron transport chain E) thylakoid space

A

63) In C4 photosynthesis, carbon fixation takes place in the ________ cells, and then is transferred as malic or aspartic acid to ________ cells, where carbon dioxide is released for entry into the Calvin cycle. A) mesophyll; bundle-sheath B) stomatal; mesophyll C) bundle-sheath; epidermal D) epidermal; mesophyll E) stomatal; epidermal

A

69) In C3 plants the conservation of water promotes A) photorespiration. B) the light reactions. C) a shift to C4 photosynthesis. D) the opening of stomata. E) photosynthesis.

A

8) Where does the Calvin cycle take place? A) stroma of the chloroplast B) thylakoid membrane C) cytoplasm surrounding the chloroplast D) chlorophyll molecule E) outer membrane of the chloroplast

A

9) A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are not being absorbed by this pigment? A) red and yellow B) blue and violet C) green and yellow D) blue, green, and red E) green, blue, and violet

A

10) During photosynthesis, visible light has enough energy to A) force electrons closer to the nucleus. B) excite electrons. C) split a water molecule into hydrogen and oxygen. D) B and C only. E) A, B, and C.

B

16) In the thylakoid membranes, what is the main role of the antenna pigment molecules? A) split water and release oxygen to the reaction-center chlorophyll B) harvest photons and transfer light energy to the reaction-center chlorophyll C) synthesize ATP from ADP and Pi D) transfer electrons to ferredoxin and then NADPH E) concentrate photons within the stroma

B

23) Some photosynthetic organisms contain chloroplasts that lack photosystem II, yet are able to survive. The best way to detect the lack of photosystem II in these organisms would be A) to determine if they have thylakoids in the chloroplasts. B) to test for liberation of O2 in the light. C) to test for CO2 fixation in the dark. D) to do experiments to generate an action spectrum. E) to test for production of either sucrose or starch.

B

32) Which of the following statements best describes the relationship between photosynthesis and respiration? A) Respiration is the reversal of the biochemical pathways of photosynthesis. B) Photosynthesis stores energy in complex organic molecules, while respiration releases it. C) Photosynthesis occurs only in plants and respiration occurs only in animals. D) ATP molecules are produced in photosynthesis and used up in respiration. E) Respiration is anabolic and photosynthesis is catabolic.

B

36) reduction of oxygen which forms water A. photosynthesis B. respiration C. both photosynthesis and respiration D. neither photosynthesis nor respiration

B

46) All of the following statements are correct regarding the Calvin cycle except: A) The energy source utilized is the ATP and NADPH obtained through the light reaction. B) These reactions begin soon after sundown and end before sunrise. C) The 5-carbon sugar RuBP is constantly being regenerated. D) One of the end products is glyceraldehyde phosphate. E) Rubisco attaches carbon dioxide to ribulose bisphosphate.

B

48) requires ATP A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

B

51) produces three-carbon sugars A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

B

53) requires CO2 A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

B

58) Referring to Figure 10.2, oxygen would inhibit the CO2 fixation reactions in A) cell I only. B) cell II only. C) neither cell I nor cell II. D) both cell I and cell II. E) cell I during the night and cell II during the day.

B

59) In which cell would you expect photorespiration? A) Cell I B) Cell II C) Cell I at night D) Cell II at night E) neither Cell I nor Cell II

B

6) What is the primary function of the light reactions of photosynthesis? A) to produce energy-rich glucose from carbon dioxide and water B) to produce ATP and NADPH C) to produce NADPH used in respiration D) to convert light energy to the chemical energy of PGAL E) to use ATP to make glucose

B

61) Why are C4 plants able to photosynthesize with no apparent photorespiration? A) They do not participate in the Calvin cycle. B) They use PEP carboxylase to initially fix CO2. C) They are adapted to cold, wet climates. D) They conserve water more efficiently. E) They exclude oxygen from their tissues.

B

64) Photorespiration lowers the efficiency of photosynthesis by preventing the formation of A) carbon dioxide molecules. B) 3-phosphoglycerate molecules C) ATP molecules. D) ribulose bisphosphate molecules. E) RuBP carboxylase molecules.

B

66) Carbon fixation involves the addition of carbon dioxide to A) rubisco. B) RuBP. C) G3P. D) 3-PGA. E) NADPH.

B

18) All of the events listed below occur in the light reactions of photosynthesis except A) oxygen is produced. B) NADP+ is reduced to NADPH. C) carbon dioxide is incorporated into PGA. D) ADP is phosphorylated to yield ATP. E) light is absorbed and funneled to reaction-center chlorophyll a.

C

20) Which statement regarding events in the functioning of photosystem II is false? A) Light energy excites electrons in an antenna pigment in a photosynthetic unit. B) The excitation is passed along to a molecule of P680 chlorophyll in the photosynthetic unit. C) The P680 chlorophyll donates a pair of protons to NADPH, which is thus converted to NADP+. D) The electron vacancies in P680 are filled by electrons derived from water. E) The splitting of water yields molecular oxygen as a by-product.

C

26) As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADPH. Where did the extra ATP molecules come from? A) photosystem II B) photosystem I C) cyclic electron flow D) noncyclic electron flow E) chlorophyll

C

65) Plants that fix CO2 into organic acids at night when the stomata are open and carry out the Calvin cycle during the day when the stomata are closed are called A) C3 plants. B) C4 plants. C) CAM plants. D) B and C only. E) A, B, and C

C

68) How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose? A) 2 B) 4 C) 6 D) 8 E) 10

C

70) C4 plants differ from C3 and CAM plants in that C4 plants A) open their stomata only at night. B) are better adapted to wet conditions. C) transfer fixed carbon dioxide to cells in which the Calvin cycle occurs. D) use malic acid to transfer carbon dioxide to the Calvin cycle. E) use PEP carboxylase to fix carbon dioxide.

C

43) Which of the following is (are) required in the Calvin cycle? A) CO2 B) ATP C) RuBP D) A and B only E) A, B, and C

E

5) Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle? A) CO2 and glucose B) H2O and O2 C) ADP, Pi, and NADP+ D) electrons and H+ E) ATP and NADPH

E

7) 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

E

28) What does the chemiosmotic process in chloroplasts 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 thylakoid space from the stroma E) formation of glucose, using carbon dioxide, NADPH, and ATP

A

40) Which of the following statements best represents the relationships between the light reactions and the Calvin cycle? A) The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, Pi, and NADP+ to the light reactions. B) The light reactions provide ATP and NADPH to the carbon fixation step of the Calvin cycle, and the cycle provides water and electrons to the light reactions. C) The light reactions supply the Calvin cycle with CO2 to produce sugars, and the Calvin cycle supplies the light reactions with sugars to produce ATP. D) The light reactions provide the Calvin cycle with oxygen for electron flow, and the Calvin cycle provides the light reactions with water to split. E) There is no relationship between the light reactions and the Calvin cycle.

A

47) produces molecular oxygen (O2) A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

A

50) produces NADPH A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

A

56) What are the substrates (normal reactants) for the enzyme RuBP carboxylase? A) CO2 and O2 B) CO2 and glucose C) ATP and NADPH D) triose-P, glucose, and CO2 E) CO2 and ATP

A

62) CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they A) fix CO2 into organic acids during the night. B) fix CO2 into sugars in the bundle-sheath cells. C) fix CO2 into pyruvate in the mesophyll cells. D) use the enzyme phosphofructokinase, which outcompetes rubisco for CO2. E) use photosystems I and II at night.

A

17) The reaction-center chlorophyll of photosystem I is known as P700 because A) there are 700 chlorophyll molecules in the center. B) this pigment is best at absorbing light with a wavelength of 700 nm. C) there are 700 photosystem I components to each chloroplast. D) it absorbs 700 photons per microsecond. E) the plastoquinone reflects light with a wavelength of 700 nm.

B

24) What are the products of noncyclic photophosphorylation? A) heat and fluorescence B) ATP and P700 C) ATP and NADPH D) ADP and NADP E) P700 and P680

C

31) 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.

C

35) synthesis of ATP by the chemiosmotic mechanism A. photosynthesis B. respiration C. both photosynthesis and respiration D. neither photosynthesis nor respiration

C

39) generation of proton gradients across membranes A. photosynthesis B. respiration C. both photosynthesis and respiration D. neither photosynthesis nor respiration

C

44) Which statement is false? A) Thylakoid membranes contain the photosynthetic pigments. B) The O2 released during photosynthesis comes from water. C) RuBP is produced during cyclic electron flow in the light reactions of photosynthesis. D) The light reactions of photosynthesis provide the energy for the Calvin cycle. E) When chlorophyll is reduced, it gains electrons.

C

52) inactive in the dark A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

C

14) Figure 10.1 shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different? A) Green and yellow wavelengths inhibit the absorption of red and blue wavelengths. B) Bright sunlight destroys photosynthetic pigments. C) Oxygen given off during photosynthesis interferes with the absorption of light. D) Other pigments absorb light in addition to chlorophyll a. E) Aerobic bacteria take up oxygen which changes the measurement of the rate of photosynthesis.

D

30) In a plant cell, where are the ATP synthase complexes located? A) thylakoid membrane B) plasma membrane C) inner mitochondrial membrane D) A and C E) A, B, and C

D

38) the splitting of carbon dioxide to form oxygen gas and carbon compounds A. photosynthesis B. respiration C. both photosynthesis and respiration D. neither photosynthesis nor respiration

D

45) One carbon dioxide molecule reacts in each "turn" of the Calvin cycle. How many turns of the cycle are required for the synthesis of one glucose molecule? A) 1 B) 2 C) 3 D) 6 E) 12

D

49) produces NADH A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

D

55) Which of the following is (are) true of the enzyme ribulose bisphosphate carboxylase? A) It participates in the Calvin cycle. B) It catalyzes a phosphorylation reaction. C) It has an affinity for both O2 and CO2. D) A and C are true. E) A, B, and C are true.

D

19) Which of the following statements about the light reactions of photosynthesis are true? A) The splitting of water molecules provides a source of electrons. B) Chlorophyll (and other pigments) absorb light energy, which excites electrons. C) ATP is generated by photophosphorylation. D) Only A and C are true. E) A, B, and C are true.

E

4) If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (18O), later analysis will show that all but one of the following compounds produced by the algae contain the 18O label. That one exception is A) PGA. B) PGAL. C) glucose. D) RuBP. E) O2.

E

42) What is the primary function of the Calvin cycle? A) use ATP to release carbon dioxide B) use NADPH to release carbon dioxide C) split water and release oxygen D) transport RuBP out of the chloroplast E) synthesize simple sugars from carbon dioxide

E

21) All of the following are directly associated with photosystem II except A) extraction of hydrogen electrons from the splitting of water. B) release of oxygen. C) harvesting of light energy by chlorophyll. D) NADP+ reductase. E) P680 reaction-center chlorophyll.

D

22) All of the following are directly associated with photosystem I except A) harvesting of light energy by chlorophyll. B) receiving electrons from plastocyanin. C) P700 reaction-center chlorophyll. D) extraction of hydrogen electrons from the splitting of water. E) passing electrons to ferredoxin.

D

27) Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes? A) the splitting of water B) the absorption of light energy by chlorophyll C) the flow of electrons from photosystem II to photosystem I D) the synthesis of ATP E) the reduction of NADP+

D

34) Of the following, what do both mitochondria and chloroplasts have in common? A) thylakoid membranes B) chemiosmosis C) ATP synthase D) B and C only E) A, B, and C

D

54) requires glucose A. light reactions alone B. the Calvin cycle alone C. both the light reactions and the Calvin cycle D. neither the light reactions nor the Calvin cycle E. occurs in the chloroplast but is not part of photosynthesis

D

57) Which of the following statements is true concerning Figure 10.2? A) It represents cell processes involved in C4 photosynthesis. B) It represents the type of cell structures found in CAM plants. C) It represents an adaptation that minimizes photorespiration. D) A and C are true. E) A, B, and C are true.

D

67) After 3-PGA is phosphorylated, it is reduced by A) NADP+. B) ADP. C) CO2. D) NADPH. E) ATP.

D