Bio Test 3

1) Which of the following statements regarding photosynthesis and cellular respiration is true? A) Photosynthesis occurs in chloroplasts, and cellular respiration occurs in mitochondria. B) Photosynthesis occurs in mitochondria, and cellular respiration occurs in chloroplasts. C) Photosynthesis occurs in mitochondria and in chloroplasts. D) Cellular respiration occurs in mitochondria and in chloroplasts.

2) How do cells capture the energy released by cellular respiration? A) They produce ATP. B) They produce glucose. C) They store it in molecules of carbon dioxide. D) The energy is coupled to oxygen.

3) The processes of photosynthesis and cellular respiration are complementary. During these energy conversions, some energy is A) lost in the form of heat. B) used to create light. C) destroyed when the chemical bonds of glucose are made. D) saved in the chemical bonds of water, CO2 and O2.

4) Respiration ________, and cellular respiration ________. A) produces ATP; is gas exchange B) is gas exchange; produces ATP C) produces glucose; produces oxygen D) uses glucose; produces glucose

5) Which of the following are products of cellular respiration? A) oxygen and carbon dioxide B) energy to make ATP and carbon dioxide C) oxygen and glucose D) oxygen and energy to make ATP

6) Which of the following statements regarding cellular respiration is false? A) Cellular respiration is a single chemical reaction with just one step. B) Cellular respiration produces water. C) Cellular respiration produces carbon dioxide. D) Cellular respiration releases heat.

7) The overall equation for the cellular respiration of glucose is A) C5H12O6 + 6 O2 → 5 CO2 + 6 H2O + energy. B) 5 CO2 + 6 H2O → C5H12O6 + 6 O2 + energy. C) C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy. D) C6H12O6 + energy → 6 CO2+ 6 H2O + 6 O2.

8) Which of the following statements about the energy yields from cellular respiration is true? A) Cellular respiration is more efficient at harnessing energy from glucose than car engines are at harnessing energy from gasoline. B) Cellular respiration converts all of the energy in glucose into high-energy ATP bonds. C) Cellular respiration converts the kinetic energy of glucose into chemical energy. D) The heat produced during cellular respiration is only a tiny fraction of the chemical energy available in a glucose molecule.

9) Humans use the calories they obtain from ________ as their source of energy. A) food B) water C) sunlight D) minerals

10) Humans use about ________ of their daily calories to maintain brain cells and power other life-sustaining activities. A) 25% B) 50% C) 75% D) 90%

11) A kilocalorie is defined as A) the quantity of glucose needed to increase the body temperature by 1°C. B) the quantity of heat needed to raise the temperature of 1 kg of water by 1°C. C) the quantity of food used to maintain normal bodily functions. D) the quantity of food consumed during a given type of exercise.

12) The label on the box of breakfast cereal lists one serving as containing "200 Calories" per serving. How many calories are actually in one serving? A) 20 B) 2,000 C) 200,000 D) 2,000,000

13) During cellular respiration, the energy in glucose A) becomes stored in molecules of ammonia. B) is used to manufacture glucose. C) is released all at once. D) is carried by electrons.

14) During redox reactions, A) the loss of electrons from one substance is called reduction. B) a substance that gains electrons is said to be oxidized. C) electrons are lost from one substance and added to another substance. D) protons from one molecule replace the electrons lost from another molecule.

15) Oxidation is the ________, and reduction is the ________. A) gain of electrons; loss of electrons B) loss of electrons; gain of electrons C) gain of oxygen; loss of oxygen D) gain of protons; loss of protons Answer: B

16) In biological systems, an important enzyme involved in the regulation of redox reactions is A) glucose. B) dehydrogenase. C) oxygen. D) ATP.

17) During cellular respiration, NADH A) is chemically converted into ATP. B) is reduced to form NAD+. C) delivers its electron load to the first electron carrier molecule. D) is the final electron acceptor.

18) Which of the following statements regarding the movement of electrons during cellular respiration is true? A) Electrons tend to move away from O2. B) O2 is eventually oxidized by the electrons to form water. C) The electrons release large amounts of energy each time they are transferred from one molecule to another. D) O2 is reduced when it accepts electrons and forms water.

19) The functioning of an electron transport chain is analogous to A) a Slinky toy going down a flight of stairs. B) a canoe going over a waterfall. C) a person climbing a flight of stairs one step at a time. D) a person leaping from the top to the bottom of a flight of stairs in one jump.

20) Which of the following options lists the stages in cellular respiration in the correct order? A) glycolysis, the citric acid cycle, and oxidative phosphorylation B) glycolysis, oxidative phosphorylation, and the citric acid cycle C) the citric acid cycle, oxidative phosphorylation, and glycolysis D) oxidative phosphorylation, glycolysis, and the citric acid cycle

21) A drug is tested in the laboratory and is found to create holes in both mitochondrial membranes. Scientists suspect that the drug will be harmful to human cells because it will inhibit A) the citric acid cycle. B) oxidative phosphorylation. C) glycolysis. D) the citric acid cycle and oxidative phosphorylation.

22) During which of the following phases of cellular respiration does substrate-level phosphorylation take place? A) glycolysis B) the citric acid cycle C) oxidative phosphorylation D) glycolysis and the citric acid cycle

23) Which of the following metabolic pathways is common in aerobic and anaerobic metabolism? A) the citric acid cycle B) oxidative phosphorylation C) glycolysis D) electron transport chain

24) As a result of glycolysis, there is a net gain of ________ ATP(s). A) 0 B) 1 C) 2 D) 36

25) How many molecules of NADH are produced during glycolysis? A) 2 B) 4 C) 6 D) 8

26) Which of the following is a result of glycolysis? A) production of CO2 B) conversion of glucose to two three-carbon compounds C) a net loss of two ATPs per glucose molecule D) conversion of NADH to NAD+

27) A culture of bacteria is fed glucose containing radioactive carbon and is then examined. As the bacteria metabolize the glucose, the radioactive carbon will appear first in A) carbon dioxide. B) glucose-6-phosphate. C) pyruvate. D) ATP.

28) The end products of glycolysis include A) NADH. B) acetyl CoA. C) citric acid. D) O2.

29) Pyruvate A) forms at the end of glycolysis. B) is the molecule that starts the citric acid cycle. C) is the end product of oxidative phosphorylation. D) is a six-carbon molecule.

30) After glycolysis but before the citric acid cycle, A) pyruvate is oxidized. B) a carbon atom is added to pyruvate to make a four-carbon compound. C) coenzyme A is cleaved off pyruvate. D) glucose is split, producing two molecules of pyruvate.

31) Which of the following statements regarding the chemical grooming of pyruvate is false? A) Two molecules of pyruvate are each converted into two-carbon molecules joined to a coenzyme A molecule. B) Each pyruvate loses a carbon atom, which is released as CO2. C) Two pyruvate molecules together contain less chemical energy than was found in the original glucose molecule. D) Each pyruvate molecule has a CO2 added and then joins with an NADH.

32) The enzymes of the citric acid cycle are located in the

33) The end products of the citric acid cycle include all of the following except A) CO2. B) pyruvate. C) ATP. D) FADH2.

34) The function of coenzyme A in the citric acid cycle is most like A) a limousine driver dropping off a couple at the school prom. B) a frog that turns into a prince. C) a kid jumping up and down on a trampoline. D) throwing a baited hook into a lake and catching a fish.

35) A culture of bacteria is fed glucose containing radioactive carbon and is then examined. During the citric acid cycle, radioactive carbon would first appear in A) NADH. B) citrate. C) oxaloacetate. D) CO2.

36) At the end of the citric acid cycle, most of the energy remaining from the original glucose is stored in A) CO2. B) pyruvate. C) ATP. D) NADH.

37) During chemiosmosis, A) energy is released as H+ ions move freely across mitochondrial membranes. B) ATP is synthesized when H+ ions move through a channel in ATP synthase. C) a concentration gradient is generated when large numbers of H+ ions are passively transported from the matrix of the mitochondrion to the mitochondrion's intermembrane space. D) H+ ions serve as the final electron acceptor.

38) Which of the following statements about the inner mitochondrial membrane is false? A) ATP synthase is found in the inner mitochondrial membrane. B) The inner mitochondrial membrane plays a role in the production of pyruvate. C) Electron carriers are found in the inner mitochondrial membrane. D) A gradient of H+ exists across the inner mitochondrial membrane.

39) The mitochondrial cristae are an adaptation that A) permits the expansion of mitochondria as oxygen accumulates in the mitochondrial matrix. B) helps mitochondria divide during times of greatest cellular respiration. C) increases the space for more copies of the electron transport chain and ATP synthase complexes. D) carefully encloses the DNA housed within the mitochondrial matrix.

40) A mutant protist is found in which some mitochondria lack an inner mitochondrial membrane. Which of the following pathways would be completely disrupted in these mitochondria? A) oxidative phosphorylation B) alcoholic fermentation C) glycolysis D) biosynthesis

41) If you were able to stop the process of cellular respiration after completing electron transport but prior to chemiosmosis, you would find the pH of a mitochondrion to be at its lowest A) on the outer membrane. B) on the inner membrane. C) in the mitochondrial matrix. D) in the intermembrane space.

42) By-products of cellular respiration include A) oxygen and heat. B) carbon dioxide and water. C) FADH2 and NADH. D) NADH and ATP.

43) In the electron transport chain, the final electron acceptor is A) an oxygen atom. B) a molecule of carbon dioxide. C) a molecule of water. D) ADP.

44) Rotenone is a poison commonly added to insecticides. Rotenone binds tightly with one of the electron carrier molecules in the electron transport chain, preventing electrons from passing to the next carrier molecule. Insects exposed to rotenone will die because A) they will no longer be able to perform anaerobic respiration. B) high levels of fermentation products will build up in their bodies. C) they will no longer be able to produce adequate amounts of ATP. D) they will no longer be able to absorb water and will become dehydrated.

45) As electrons move through the mitochondrial space, A) NADH is reduced. B) water is oxidized. C) ATP synthase works by active transport. D) the pH of the intermembrane space decreases.

46) Which of the following statements about the energy yield of aerobic respiration is false? A) Less than 50% of the chemical energy available in glucose is converted to ATP energy. B) Most of the ATP derived during aerobic respiration results from oxidative phosphorylation. C) Oxidative phosphorylation resulting from 1 glucose molecule yields about 12 ATP molecules. D) The total yield of ATP molecules per glucose molecule is about 32.

47) The energy yield from the breakdown of a single molecule of glucose does not depend upon A) whether the NADH produced in glycolysis passes its electrons across the mitochondrial membrane to NAD+ or FAD. B) the supply of oxygen. C) the supply of carbon dioxide. D) whether some of the energy of the H+ gradient is used for work other than ATP production.

48) Which of the following processes produces the most ATP per molecule of glucose oxidized? A) aerobic respiration B) alcoholic fermentation C) lactic acid fermentation D) All produce approximately the same amount of ATP per molecule of glucose.

49) In fermentation, ________ is ________. A) NADH; reduced B) NAD+; oxidized C) NADH; oxidized D) ethanol; oxidized

50) When an organism such as a yeast lives by fermentation, it converts the pyruvate from glycolysis into a different compound, such as alcohol. Why doesn't it secrete the pyruvate directly? A) The conversion yields 32 ATP per pyruvate molecule. B) The conversion yields one NADH per pyruvate molecule. C) The conversion is needed to regenerate the molecules needed for glycolysis. D) A buildup of pyruvate in the surrounding environment would be too toxic.

51) A child is born with a rare disease in which mitochondria are missing from skeletal muscle cells. However, the muscles still function. Physicians find that A) the muscles contain large amounts of lactate following even mild physical exercise. B) the muscles contain large amounts of carbon dioxide following even mild physical exercise. C) the muscles require extremely high levels of oxygen to function. D) the muscle cells cannot split glucose to pyruvate.

52) Some friends are trying to make wine in their basement. They've added yeast to a sweet grape juice mixture and have allowed the yeast to grow. After several days they find that sugar levels in the grape juice have dropped, but there's no alcohol in the mixture. The most likely explanation is that A) the mixture needs more sugar because yeast need a lot of energy before they can begin to produce alcohol. B) the mixture needs less oxygen because yeast only produce alcohol in the absence of oxygen. C) the mixture needs more oxygen because yeast need oxygen to break down sugar and get enough energy to produce alcohol. D) the yeast used the alcohol as a carbon source.

53) In yeast cells, A) lactic acid is produced during anaerobic respiration. B) lactic acid is produced during glycolysis. C) alcohol is produced during the citric acid cycle. D) alcohol is produced after glycolysis.

54) Bacteria that are unable to survive in the presence of oxygen are called A) obligate anaerobes. B) obligate aerobes. C) facultative anaerobes. D) aerotolerant anaerobes.

55) Yeasts can produce ATP by either fermentation or oxidative phosphorylation; thus, they are A) strict anaerobes. B) strict aerobes. C) facultative anaerobes. D) facultative aerobes.

56) When did the level of oxygen in Earth's atmosphere become high enough to sustain aerobic respiration? A) 1.0 billion years ago B) 1.5 billion years ago C) 2.7 billion years ago D) 3.5 billion years ago

57) Which of the following statements regarding glycolysis is false? A) Glycolysis is considered to be an ancient metabolic process because it does not require oxygen. B) Glycolysis is considered to be an ancient metabolic process because it is not located in a membrane-bound organelle. C) Glycolysis is considered to be an ancient metabolic system because it occurs universally. D) Glycolysis is considered to be an ancient metabolic system because it is the most efficient metabolic pathway for ATP synthesis.

58) To obtain energy from starch and glycogen, the body must begin by A) hydrolyzing the starch to glucose and the glycogen to amino acids. B) hydrolyzing both starch and glycogen to glucose. C) converting both starch and glycogen to fatty acids. D) removing one glucose at a time with a condensation reaction.

59) When proteins are used as a source of energy for the body, the proteins A) are converted into glucose molecules, which are fed into glycolysis. B) are converted mainly into intermediates of glycolysis or the citric acid cycle. C) donate electrons directly to the electron transport chain. D) are hydrolyzed to glucose and converted to acetyl CoA, which enters the citric acid cycle.

60) When a cell uses fatty acids for aerobic respiration, it first hydrolyzes fats to A) glycerol and amino acids. B) glycerol and fatty acids. C) fatty acids and sugars. D) sugars and glycerol.

61) If you consume 1 g of each of the following, which will yield the most ATP? A) fat B) glucose C) protein D) starch

62) Which of the following statements regarding food is false? A) Food provides the raw materials for biosynthetic pathways that make molecules for cellular repair and growth. B) Food provides the raw materials for biosynthetic pathways that can produce molecules that are not actually present in the original food. C) Food provides the raw materials for biosynthetic pathways that can produce sugar by a process that is the exact opposite of glycolysis. D) Food provides the raw materials for biosynthetic pathways that consume ATP.

63) Which of the following organisms can make organic molecules from water and carbon dioxide? A) bear B) mushroom C) wheat D) crayfish

64) The conversion of CO2 and H2O into organic compounds using energy from light is called A) glycolysis. B) photosynthesis. C) fermentation. D) cellular respiration.

65) If ATP accumulates in a cell, A) the cell receives a signal that there is a need for more energy. B) feedback inhibition speeds up cellular respiration. C) feedback inhibition slows down cellular respiration. D) the rate of cellular respiration does not change.

66) The antibiotic oligomycin works by inhibiting ATP synthase. You would expect that A) there will be an increase in ATP production. B) H+ will accumulate in the intermembrane space. C) H+ will accumulate in the mitochondrial matrix. D) NAD+ and FAD will pick up the extra H+.

67) The Pasteur effect shows that yeast consume glucose at a higher rate under anaerobic conditions than under aerobic conditions. Which of the following statements correctly explains this observation? A) Yeast are obligate anaerobes, so aerobic conditions will kill yeasts. B) Yeast are photosynthetic, so they are able to produce their own oxygen. C) Less ATP is made under anaerobic conditions, so more glucose must be consumed to produce an equivalent amount of ATP. D) This observation is incorrect. Aerobic conditions mean that cells make more ATP and use more glucose.

68) DNP is a chemical that has been used by people to lose weight. However, it is a dangerous option and has caused several people to die. DNP works in a fashion similar to that of brown fat. Based on this information, how would DNP cause weight loss and death? A) DNP must prevent food from being consumed aerobically, so cells instead perform fermentation, and lactate buildup is deadly. B) DNP must increase the rate of substrate-level phosphorylation, causing NADH to be produced more quickly than it can be used by the electron transport chain. C) DNP must block cells from using fats and proteins to make ATP. D) DNP must increase metabolism of food by producing heat instead of ATP.

69) A friend tells you that he is going on a low-carb diet to lose weight because he thinks that carbs contain more energy than fats or protein. What would you tell your friend about his plan? A) This is a good idea because sugars enter the fuel breakdown pathway earlier than other food molecules. B) This is a good idea because sugars have more electrons than fats and protein. C) This is an incorrect idea because fats contain more hydrogen atoms than carbohydrates and protein. D) This is an incorrect idea because all food molecules store the same amount of energy.

70) Marathon runners are long-distance runners (marathons are races that are 26.2 miles long). Studies have shown that the muscles of marathon runners contain an abundance of slow-twitch fibers. Which of the following statements about these fibers is true? A) Slow-twitch fibers have lots of mitochondria to make ATP aerobically. B) Slow-twitch fibers have lots of mitochondria to make ATP through fermentation. C) Slow-twitch fibers have few mitochondria and make ATP aerobically. D) Slow-twitch fibers have few mitochondria and make ATP through fermentation.

71) Wood frogs freeze solid during the winter and then thaw in the spring. As the freezing progresses, blood circulation stops. How would you expect cells not being served by the circulatory system to produce ATP during this time, and what by-product would you expect to build up in the cells? A) aerobic respiration and CO2 B) fermentation and lactate C) fermentation and alcohol D) photosynthesis and O2

72) Arsenic is a poison that binds to a molecule needed to build acetyl CoA. Based on this information, which part of cellular respiration would be stopped if arsenic were ingested? A) glycolysis B) citric acid cycle C) electron transport chain D) ATP synthase

73) NADH pills can be purchased over the counter and are often taken by sufferers of chronic fatigue syndrome (CFS). How might these pills benefit a CFS patient? A) They would increase energy by creating more FADH2. B) They would decrease the rate of glycolysis. C) They would increase the number of electrons provided to the electron transport chain. D) They would decrease the rate of alcoholic fermentation.

74) NADH is also used by cells when making certain molecules. Based on your knowledge of NADH's role in cellular respiration, what do you think NADH's role is in biosynthesis of molecules? A) oxidizing molecules B) reducing molecules C) phosphorylating molecules D) dehydrating molecules

75) Which of the following statements about the energy yield of aerobic respiration is false? A) Glycolysis resulting from 1 glucose molecule yields 2 ATP molecules. B) The oxidation of pyruvate results in the production of 0 ATP molecules C) Oxidative phosphorylation resulting from 1 glucose molecule yields 12 ATP molecules. D) The citric acid cycle resulting from 1 glucose molecules yields 2 ATP molecules.

2) Which H+ has just passed through the inner mitochondrial membrane by diffusion? A) hydrogen ion A B) hydrogen ion B C) hydrogen ion C D) hydrogen ion D

1) Which step of the citric acid cycle requires both NAD+ and ADP as reactants? A) step 1 B) step 2 C) step 3 D) step 4

3) Based on this graph, what is the relationship between metabolic rate and body temperature? A) When metabolic rate drops, so does body temperature. B) When metabolic rate drops, body temperature rises. C) When metabolic rate drops, body temperature remains constant. D) There is no relationship between metabolic rate and body temperature.

4) Why does the relationship between metabolic rate and temperature exist? A) Cellular respiration requires organisms to take in heat energy. B) A by-product of cellular respiration is heat. C) Cellular respiration causes the body to cool because all the energy is used to make ATP. D) There is no relationship between metabolic rate and body temperature.

5) Bats contain brown fat between their shoulder blades. How could this brown fat be an adaptation to torpor? A) Brown fat has many mitochondria, so it can produce more ATP. B) Brown fat can produce heat and ATP through fermentation. C) The mitochondria in brown fat can produce heat without making ATP. D) It is not an adaptation; white fat is what they need to produce heat.

1) Fat Away prevents ATP from being made by A) destroying the H+ gradient that allows ATP synthase to work. B) preventing glycolysis from occurring. C) preventing the conversion of NADH to NAD+. D) slowing down the citric acid cycle.

2) You predict that a side effect of Fat Away will be A) increased production of NADH. B) increased production of pyruvate. C) increased production of lactate. D) increased body temperature.

1) What is the name given to organisms that can make their own food and thus sustain themselves without consuming organic molecules derived from other organisms? A) chemotrophs B) heterotrophs C) synthesizers D) autotrophs

2) Photoautotrophs A) make sugar by using organic raw materials. B) produce organic molecules from inorganic molecules. C) eat other organisms that use light energy to make food molecules. D) include only the green plants.

3) Which of the following is an example of a photoautotroph? A) algae in freshwater and marine ecosystems B) grizzly bears in Alaska C) bacteria in our mouth D) mushrooms growing on the side of a dead tree

4) Autotrophs that utilize light as their energy source are A) chemosynthetic autotrophs. B) photoautotrophs. C) fungi. D) heterotrophs.

5) What is the likely origin of chloroplasts? A) mitochondria that had a mutation for photosynthesis B) photosynthetic prokaryotes that lived inside eukaryotic cells C) prokaryotes with photosynthetic mitochondria D) eukaryotes that engulfed photosynthetic fungi

6) In most green plants, chloroplasts are A) concentrated in a zone of leaf tissue called the mesophyll. B) concentrated in a portion of the leaf called the stroma. C) evenly distributed throughout the leaf tissue. D) evenly distributed throughout the entire plant.

7) ________ cells in leaves are specialized for photosynthesis. A) Companion B) Mesophyll C) Sclerenchyma D) Tracheid

8) CO2 enters and O2 escapes from a leaf via A) stomata. B) thylakoids. C) grana. D) stroma.

9) In the chloroplast, sugars are made in a compartment that is filled with a thick fluid called the A) stomata. B) thylakoid. C) matrix. D) stroma.

10) Thylakoids are arranged in stacks called A) cristae. B) stomata. C) grana. D) vacuoles.

11) Where is chlorophyll found in a plant cell? A) stroma B) thylakoid membranes C) cytoplasm D) cristae

12) The oxygen released into the air as a product of photosynthesis comes from A) water. B) glucose. C) carbon dioxide. D) chlorophyll.

13) Which of the following molecules is a reactant of photosynthesis? A) CO2 B) glucose C) O2 D) chlorophyll

14) If you expose a photosynthesizing plant to water that contains both radioactive H and radioactive O, in which of the products of photosynthesis will the radioactive H and O show up? A) H and O both in glucose B) H in glucose; O in water C) H in water; O in glucose D) H in glucose and water; O in O2

15) A redox reaction involves the transfer of A) oxygen. B) water. C) an electron. D) carbon dioxide.

16) Which of the following statements concerning the role of redox reactions in photosynthesis and cellular respiration is true? A) Photosynthesis involves only reductions, whereas respiration involves only oxidations. B) Photosynthesis involves only oxidations, whereas respiration involves only reductions. C) In photosynthesis, carbon dioxide is oxidized to form sugar, whereas in respiration, sugar is reduced to form carbon dioxide. D) In photosynthesis, carbon dioxide is reduced to form sugar, whereas in respiration, sugar is oxidized to form carbon dioxide.

17) What is the source of energy that provides the boost for electrons during photosynthesis? A) light B) NADPH C) cellular respiration D) ATP

18) Which of the following statements comparing photosynthesis and cellular respiration is false? A) ATP is not produced during photosynthesis; it is produced only during cellular respiration. B) Photosynthesis is ultimately powered by light energy and respiration by the chemical energy of fuel molecules. C) Photosynthesis consumes CO2; respiration consumes O2. D) Photosynthesis produces O2; respiration produces CO2.

19) The light reactions occur in the ________, while the Calvin cycle occurs in the ________. A) stroma; thylakoid membranes B) stroma; nucleus C) cytoplasm; thylakoid membrane D) thylakoid membranes; stroma

20) Which of the following are produced during the light reactions of photosynthesis? A) glucose, ADP, NADP+ B) glucose, ADP, NADP+, CO2 C) ADP, NADP+, O2 D) ATP, NADPH, O2

21) Which of the following is part of the light reaction? A) carbon fixation B) reduction of carbon C) regeneration of NADP+ D) formation of waste products in the form of O2

22) Which of the following are produced during the Calvin cycle? A) glucose, ADP, NADP+ B) glucose, ADP, NADP+, CO2 C) ATP, NADPH, O2 D) ATP, NADPH, CO2

23) Carbon fixation A) occurs when carbon atoms from CO2 are incorporated into an organic molecule. B) supplies the cell with ATP. C) occurs during the light reactions. D) provides the cell with a supply of NADPH molecules. Answer: A

24) Sunlight is a type of ________ energy. A) electromagnetic B) chemical C) mechanical D) sound

25) The full range of electromagnetic energy is called the ________ spectrum. A) visible B) electromagnetic C) energy D) ultraviolet

26) Why are most plants green? A) Chlorophyll a reflects green light. B) Chlorophyll a absorbs green light. C) Chlorophyll b primarily uses green light as the source of energy for photosynthesis. D) Green helps plants blend into their environment as a sort of camouflage.

27) Which of the following colors contributes the least energy to photosynthesis? A) blue B) red C) orange D) green

28) Which of the following wavelengths of light would you expect to be reflected or transmitted by chlorophyll a? A) blue B) green C) yellow D) red

29) Chlorophyll b A) is best at absorbing the energy of green light. B) is best at absorbing the energy of blue-violet and red light, just like chlorophyll a. C) passes absorbed energy to chlorophyll a. D) catalyzes the incorporation of carbon atoms into RuBP.

30) Plant cells are protected from the harmful effects of excessive light energy and reactive oxidative molecules by A) mitochondria. B) chlorophyll. C) carotenoids. D) ATP.

31) A packet of light energy is called a A) quantum. B) pigment. C) photon. D) phaser.

32) Which of the following statements about the absorption of photons by pigment molecules is true? A) It takes several minutes for the pigment electrons to become excited. B) Photons raise electrons in pigments to the ground state. C) Excitation of the electrons is a very stable state. D) Energy can be released by the excited electron as heat, light, or fluorescence.

33) Which of the following photosynthetic pigments can be found at the photosystem reaction center? A) chlorophyll b B) chlorophyll a C) a carotenoid D) phycocyanin

34) Which of the following is a normal process of photosynthesis that could not occur if all reaction centers were inactivated by a toxin? A) donation of excited electrons by chlorophyll a to a primary electron acceptor B) donation of excited electrons by chlorophyll b to a primary electron acceptor C) absorption of photons by chlorophyll b D) absorption of photons by carotenoids

35) Which of the following molecules is a product of photosynthesis? A) CO2 and chlorophyll B) glucose and O2 C) O2 and CO2 D) glucose and CO2

36) Clusters of light-gathering pigments in a photosystem A) pass energy to the reaction center. B) are found in the roots of plants. C) absorb electrons. D) break down H2O.

37) In a photosystem, clusters of chlorophyll a, chlorophyll b, and carotenoid pigments function most like A) an antenna. B) a propeller on a motorboat. C) a windmill. D) a spring.

38) The energy that excites the photosystems is supplied by A) electrons passing down the electron transport chain. B) ATP. C) photons. D) NADPH.

39) The electron transport chains of the light reactions A) are located in the stroma. B) shuttle electrons from photosystem II to photosystem I. C) provide energy for the citric acid cycle. D) are found on the plasma membrane of mesophyll cells.

40) As a result of the cascade of electrons down the electron transport chains of the light reactions, A) NADPH is reduced to NADP+. B) NADPH is oxidized to NADP+. C) NADP+ is reduced to NADPH. D) NADP+ is oxidized to NADPH.

41) The electrons lost from the reaction center of photosystem I are replaced by electrons from A) CO2. B) H2O. C) ATP. D) photosystem II.

42) The electrons lost from the reaction center of photosystem II are replaced by electrons from A) CO2. B) ATP. C) H2O. D) photosystem I.

43) Photosystem II A) receives electrons from photosystem I. B) passes electrons to photosystem I. C) does not have a reaction center. D) releases CO2 as a by-product.

44) Photophosphorylation during photosynthesis differs from oxidative phosphorylation during cellular respiration in that A) it involves an electron transport chain. B) energy is stored in the form of a proton (H+) concentration difference. C) generation of ATP is driven by a flow of protons (H+) through ATP synthase. D) the final electron acceptor is NADP+ and not oxygen.

45) In photophosphorylation, energy from electron flow is used to transport ________ from the ________ to the thylakoid compartment, generating a concentration gradient of ________. A) electrons; grana; H+ B) H+; grana; electrons C) H+; stroma; H+ D) H+; stroma; ATP

46) In chloroplasts, ATP synthase A) catalyzes the Calvin cycle. B) phosphorylates ADP to ATP. C) is found in the stroma. D) helps produce the concentration gradient of H+.

47) In photosynthesis, the chemiosmotic production of ATP A) requires oxygen. B) is similar to the production of ATP in mitochondria. C) is done by the Calvin cycle. D) is a result of the oxidation of glucose.

48) Mitochondria transfer ________ energy from ________ to ATP; chloroplasts transform ________ energy into the chemical energy of ATP. A) chemical; food; light B) food; light; chemical C) light; food; kinetic D) food; light; nuclear

49) Photosynthetic organisms derive their carbon from A) carbon monoxide. B) carbon dioxide. C) hydrocarbons. D) methane.

50) ATP and NADPH A) power sugar synthesis during the Calvin cycle. B) are products of the Calvin cycle. C) provide energy to photosystem I and photosystem II. D) are used in the electron transport chain to pump H+ into the thylakoid space.

51) To produce one glucose, the Calvin cycle needs to be run ________ times. A) two B) four C) six D) eight

52) The Calvin cycle constructs ________, an energy-rich molecule that a plant cell can then use to make glucose or other organic molecules. A) G3P B) ATP C) NADH D) carbon dioxide

53) The addition of oxygen instead of carbon dioxide to RuBP results in A) cellular respiration. B) photorespiration. C) photophosphorylation. D) aerobic respiration.

54) Photorespiration A) may be an evolutionary relic from when atmospheric O2 levels were low. B) is of benefit to the plant since it breaks down rubisco. C) is attributable to high CO2 levels. D) produces glucose.

55) What is the main adaptive advantage of the C4 and CAM photosynthesis strategies over the C3 strategy? A) They help the plant synthesize glucose efficiently under dry conditions. B) They allow the plant to fix carbon under conditions of low CO2. C) They allow the plant to fix carbon in cool conditions. D) They make it possible for the plant to use the Calvin cycle at night.

56) The ultimate source of all the food we eat and the oxygen we breathe is A) cellular respiration. B) photosynthesis. C) glycolysis. D) anaerobic metabolism.

57) Plants use sugars as A) a fuel for photosynthesis. B) a starting material for the Calvin cycle. C) a source of electrons for chemiosmosis. D) a fuel for cellular respiration and a starting material for making other organic molecules.

58) Plant cells A) lack mitochondria and chloroplasts. B) lack mitochondria but have chloroplasts. C) have mitochondria but do not have chloroplasts. D) have mitochondria and chloroplasts.

59) Global warming due to the greenhouse effect may be A) moderated by photosynthesis, which removes carbon dioxide from the atmosphere. B) made worse by photosynthesis, which adds carbon dioxide to the atmosphere. C) reduced by the burning of fossil fuels, which removes oxygen from the atmosphere. D) of little concern, since it is part of the normal cycle for the planet.

60) Which of the following statements about the greenhouse effect is true? A) The greenhouse effect is reduced by deforestation. B) The greenhouse effect is exacerbated by the use of fossil fuels. C) The greenhouse effect will decrease the average temperature of the planet. D) The greenhouse effect has no direct relationship with the Industrial Revolution of the 1800s.

61) It has been argued that cutting old-growth forests and replacing them with plantations of young trees would help to alleviate the threat of global greenhouse warming. What important fact does this argument ignore? A) Forests play too minor a role in global CO2 dynamics, which are affected far more by marine algae. B) Young trees fix carbon at a lower rate per unit mass than old trees. C) Most of the biomass of the cut trees would be added to the atmosphere as CO2 within a few years. D) Most of the young trees would die within a few years.

62) Ozone A) formation is promoted by CFCs. B) is broken down by carbon dioxide. C) is a source of oxygen for cellular respiration. D) protects Earth from ultraviolet radiation.

63) Ozone consists of ________ oxygen atom(s). A) one B) two C) three D) four

64) Which of the following has been a major source of ozone destruction over the past 50 years? A) chlorofluorocarbons (CFCs) B) ethylene glycol (C2H6O2) C) carbon dioxide (CO2) D) methane (CH4)

65) Chlorophyll is located in ________, which are found in ________, which are concentrated in ________. A) thylakoids; chloroplasts; mesophyll B) chloroplasts; thylakoids; mesophyll C) mesophyll; chloroplasts; thylakoids D) mesophyll; thylakoids; chloroplasts

66) You want to use radioactively labeled oxygen to trace carbon fixation in a plant. You should incorporate the radioactively labeled oxygen into A) O2. B) CO2. C) H2O. D) C6H12O6.

67) Put the following steps of the light reactions in the correct order: 1. Light excites an electron from photosystem I. 2. Light excites an electron from photosystem II. 3. Electrons reduce NADP+ to NADPH. 4. Electrons pass through an electron transport chain, which generates a H+ gradient used to make ATP. A) 1, 2, 3, 4 B) 1, 4, 2, 3 C) 2, 4, 1, 3 D) 2, 3, 1, 4

68) Put the following steps of the Calvin cycle in the correct order: 1. Carbon fixation 2. Regeneration of RuBP 3. Release of G3P 4. Reduction A) 1, 2, 3, 4 B) 1, 3, 4, 2 C) 1, 4, 3, 2 D) 4, 1, 2, 3

69) Purple sulfur bacteria are organisms capable of photosynthesis. They get their name, in part, because they use H2S (hydrogen sulfide) instead of water during the light reactions. In what form would you expect to find sulfur (S) as a result of photosynthesis in these bacteria? A) S2 B) SO2 C) CS2 D) C6H12S6

70) Many of the regions of the world where hunger is prevalent are also regions with hot and dry climates. What types of agricultural crops would you suggest that these regions attempt to grow? A) C3 plants, such as wheat and rice B) C3 plants and C4 plants, such as corn and sugarcane C) C3 plants and CAM plants, such as prickly pear and pineapple D) C4 plants and CAM plants

71) Atrazine is a widely used herbicide that binds to a protein in photosystem II, ultimately causing a breakdown in electron transport. Atrazine would first inhibit the production of A) NADPH. B) G3P. C) ATP. D) O2.

72) Red algae are found in relatively deep water. In order for light to penetrate to these depths, it must be high in energy. Which wavelengths of light would you expect red algae to use? A) red B) yellow C) green D) blue

73) Which of the following is not an expected outcome of global climate change? A) extreme weather patterns B) lower sea levels C) spread of tropical diseases D) increased extinction rates

74) It has been suggested that global warming could be halted by fertilizing the oceans to increase the growth of algae. How might this affect the greenhouse effect? A) Algal photosynthesis would use up more CO2, which traps heat. B) Algal photosynthesis would produce more O2, which blocks light. C) Algal photosynthesis would be inhibited by the addition of fertilizer. D) Algae photosynthesis would use heat in place of photons.

1) In this drawing of a chloroplast, which structure represents the thylakoid membrane?

2) According to this figure, how do hydrogen ions make their way from the stroma to the thylakoid interior?

3) If you focus on the data from the mid-1900s (indicated by the arrow) through today, the graph shows that

4) Currently, atmospheric CO2 levels are approximately 400 ppm. The annual mean growth rate in CO2 is about 2 ppm/year. Assuming this trend continues, what would you predict the CO2 level to be in 100 years? A) 100 ppm B) 200 ppm C) 600 ppm D) 1,000 ppm

5) If the trends shown in the graph continue, how might this affect photosynthesis? A) Photorespiration may increase, leading to an increase in photosynthetic production of sugar. B) Photorespiration may increase, leading to a decrease in photosynthetic production of sugar. C) C4 and CAM plants would be unable to photosynthesize. D) There would be no effect on photosynthesis, since CO2 and temperature are stable.

1) Based on your knowledge of the process of photosynthesis, the plant in the container placed under red light would probably A) absorb no CO2. B) absorb the same amount of CO2 as the plants under the green light. C) absorb less CO2 than the plants under the green light. D) absorb more CO2 than the plants under the green light.

2) Carbon dioxide absorption is an appropriate indicator of photosynthesis because A) CO2 is needed to produce sugars in the Calvin cycle. B) CO2 is needed to complete the light reactions. C) plants produce oxygen gas by splitting CO2. D) the energy in CO2 is used to produce ATP and NADPH.