BIO CH. 7 Flashcards

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1
Q

1) The summary equation for photosynthesis is
A) 6 CO2 + 6 H2O + sunlight → C6H12O6 + 6 O2.
B) C5H12O6 + 6 O2 + sunlight → 5 CO2 + 6 H2O.
C) C6H12O6 + 6 O2 + sunlight → 6 CO2 + 6 H2O.
D) the same as the equation for glycolysis written in reverse.
E) 6 CH2O + 5 O2 + sunlight → CO2 + 2 H2O.

A

A) 6 CO2 + 6 H2O + sunlight → C6H12O6 + 6 O2.

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2
Q

Which of the following statements regarding photosynthesis and carbon dioxide is false?
A) Plants require carbon dioxide, water, and sunlight to make glucose.
B) Burning fossil fuels release carbon dioxide that was removed from the atmosphere millions of years ago.
C) Because of their short growth period and self-regeneration, willows are more viable as a source of potential power
than the trees in most natural forests.
D) Most of the food humans eat can be traced back to photosynthetic plants.
E) Burning wood contributes more to acid rain than burning fossil fuels.

A

E) Burning wood contributes more to acid rain than burning fossil fuels.

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3
Q
What is the name given to organisms that can make their own food and the food for the biosphere? 
A) chemotrophs 
B) heterotrophs 
C) manufacturers 
D) synthesizers 
E) producers
A

E) producers

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4
Q

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.
E) are only found on land.

A

B) produce organic molecules from inorganic molecules

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5
Q

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

A

A) cyanobacteria in freshwater and marine ecosystems

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6
Q
Autotrophs that utilize light as their energy source are 
A) chemosynthetic autotrophs. 
B) photoautotrophs. 
C) consumers. 
D) fungi. 
E) heterotrophs
A

B) photoautotrophs.

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7
Q

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

A

B) photosynthetic prokaryotes that lived inside eukaryotic cells

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8
Q

8) In most green plants, chloroplasts are
A) concentrated in a zone of leaf tissue called the mesophyll.
B) concentrated in the stomata.
C) concentrated in a portion of the leaf called the stroma.
D) found throughout the leaf tissue.
E) found throughout the plant.

A

A) concentrated in a zone of leaf tissue called the mesophyll.

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9
Q
) \_\_\_\_\_\_\_\_ cells in leaves are specialized for photosynthesis. 
A) Companion 
B) Mesophyll 
C) Sclerenchyma 
D) Tracheid 
E) Collenchyma
A

B) Mesophyll

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10
Q
CO2 enters and O2 escapes from a leaf via 
A) stomata. 
B) thylakoids. 
C) grana. 
D) stroma. 
E) central vacuoles
A

A) stomata.

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11
Q
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. 
E) mesophyll
A

D) stroma.

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12
Q
Chloroplasts contain disklike membranous sacs arranged in stacks called 
A) cristae. 
B) thylakoids. 
C) grana. 
D) vacuoles. 
E) stroma.
A

C) grana.

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13
Q
Where is chlorophyll found in a plant cell? 
A) stroma 
B) thylakoid membranes 
C) matrix 
D) cytoplasm 
E) cristae
A

B) thylakoid membranes

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14
Q
14) The oxygen released into the air as a product of photosynthesis comes from 
A) water. 
B) glucose. 
C) carbon dioxide. 
D) chlorophyll. 
E) mitochondria.
A

A) water.

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15
Q
15) Which of the following molecules is both a reactant and a product of photosynthesis? 
A) H2O 
B) glucose 
C) O2 
D) CO2 
E) chlorophyll
A

A) H2O

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16
Q

16) 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
E) H in glucose and water; O in water and O2

A

D) H in glucose and water; O in O2

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17
Q
A redox reaction involves the transfer of 
A) a hydrogen ion. 
B) oxygen. 
C) water. 
D) an electron. 
E) carbon dioxide
A

D) an electron.

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18
Q

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

A

D) In photosynthesis, carbon dioxide is reduced to form sugar, while in respiration, sugar is oxidized to form carbon
dioxide.

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19
Q
What is the source of energy that provides the boost for electrons during photosynthesis? 
A) light 
B) electromagnetism 
C) cellular respiration 
D) ATP 
E) glucose
A

A) light

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20
Q

Which of the following statements regarding photosynthesis is false?
A) ATP is not produced during photosynthesis, but only during 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.
E) The principal electron carrier in photosynthesis is NADPH; the principal electron carrier in respiration is NADH.

A

A) ATP is not produced during photosynthesis, but only during respiration.

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21
Q
The light reactions occur in the \_\_\_\_\_\_\_\_, while the Calvin cycle occurs in the \_\_\_\_\_\_\_\_. 
A) stroma . . . thylakoid membranes 
B) stroma . . . nucleus 
C) cytoplasm . . . stroma 
D) cytoplasm . . . thylakoid membrane 
E) thylakoid membranes . . . stroma
A

E) thylakoid membranes . . . stroma

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22
Q
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 
E) ATP, NADPH, CO2
A

D) ATP, NADPH, O2

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23
Q

Which of the following is part of the light reaction?
A) carbon fixation
B) reduction of carbon
C) addition of electrons and protons to carbon
D) regeneration of NADP+
E) formation of waste products in the form of O2

A

E) formation of waste products in the form of O2

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24
Q
Which of the following are produced during the Calvin cycle? 
A) glucose, ADP, NADP+ 
B) glucose, ADP, NADP+, CO2 
C) ADP, NADP+, O2 
D) ATP, NADPH, O2 
E) ATP, NADPH, CO2
A

A) glucose, ADP, NADP+

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25
Q

Carbon fixation
A) occurs when carbon and oxygen from CO2 are incorporated into an organic molecule.
B) powers the process of glucose synthesis by supplying the cell with ATP.
C) occurs during the light reactions.
D) provides the cell with a supply of NADPH molecules.
E) uses noncyclic electron flow to capture energy in glucose

A

A) occurs when carbon and oxygen from CO2 are incorporated into an organic molecule.

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26
Q
Sunlight is a type of \_\_\_\_\_\_\_\_ energy. 
A) electromagnetic 
B) potential 
C) stored 
D) kinetic 
E) nuclear
A

A) electromagnetic

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27
Q
The full range of electromagnetic energy is called the \_\_\_\_\_\_\_\_ spectrum. 
A) wavelength 
B) visible 
C) electromagnetic 
D) energy 
E) ultraviolet
A

C) electromagnetic

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28
Q

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.
E) All photosynthetic pigments are colored green.

A

A) Chlorophyll a reflects green light.

29
Q
Which of the following colors contributes the least energy to photosynthesis? 
A) blue 
B) red 
C) violet 
D) orange 
E) green
A

E) green

30
Q
Of the following wavelengths of light, which would you expect to be reflected or transmitted by chlorophyll a? 
A) blue 
B) green 
C) yellow 
D) orange 
E) red
A

B) green

31
Q

Chlorophyll b and carotenoids
A) are best at absorbing the energy of green light.
B) are found at the reaction center.
C) are located on the inner membrane of the chloroplast.
D) pass absorbed energy to chlorophyll a.
E) catalyze the incorporation of carbon atoms into RuBP.

A

D) pass absorbed energy to chlorophyll a.

32
Q
Plant cells are protected from the harmful effects of oxygen radicals with 
A) NADPH. 
B) mitochondria. 
C) chlorophyll. 
D) carotenoids. 
E) ATP.
A

D) carotenoids.

33
Q
) A packet of light energy is called a 
A) quantum. 
B) pigment. 
C) photon. 
D) phaser. 
E) wavelength.
A

C) photon.

34
Q

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) Pigments only lose energy in the excitation process.
D) Excitation of the electrons is a very stable state.
E) The release of energy by the excited electron can be as heat, light, or fluorescence.

A

E) The release of energy by the excited electron can be as heat, light, or fluorescence.

35
Q
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 
E) eosinophyll
A

B) chlorophyll a

36
Q

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) reduction of chlorophyll b by a primary electron acceptor
E) absorption of photons by carotenoids

A

A) donation of excited electrons by chlorophyll a to a primary electron acceptor

37
Q

How do the reaction centers of photosystem I and II differ?
A) Chlorophyll a is found in photosystem I and chlorophyll b in photosystem II.
B) Each preferentially absorbs slightly different wavelengths of light.
C) Photosystem I functions first in the sequence of steps that make up the light reactions.
D) Only photosystem I is found in the thylakoid membranes.
E) Photosystem II does not transfer electrons from photons.

A

B) Each preferentially absorbs slightly different wavelengths of light.

38
Q
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) do not absorb photons. 
E) break down H2O.
A

A) pass energy to the reaction center.

39
Q
In a photosystem, clusters of chlorophyll a, chlorophyll b, and carotenoid pigments function most like 
A) an electrical generator. 
B) an antenna. 
C) a propeller on a motorboat. 
D) a windmill. 
E) a spring.
A

B) an antenna.

40
Q

) The energy that excites P680 and P700 is supplied by
A) electrons passing down the electron transport chain.
B) the breaking of glucose bonds.
C) ATP.
D) photons.
E) NADPH.

A

D) photons.

41
Q

The electron transport chains of the light reactions
A) are located in the stroma.
B) are very different from those of cellular respiration.
C) shuttle electrons along in a series of redox reactions.
D) provide energy for the Krebs cycle.
E) are found on the inner membrane of chloroplasts

A

C) shuttle electrons along in a series of redox reactions.

42
Q
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. 
E) water is formed
A

C) NADP+ is reduced to NADPH.

43
Q

The electrons lost from the reaction center of photosystem I are replaced by electrons from
A) CO2.
B) ATP.
C) H2O.
D) the top of the electron transport chain.
E) the bottom of the electron transport chain

A

E) the bottom of the electron transport chain

44
Q
The electrons lost from the reaction center of photosystem II are replaced by electrons from 
A) CO2. 
B) ATP. 
C) H2O. 
D) NADPH. 
E) photosystem I.
A

C) H2O.

45
Q
Photosystem II 
A) has P700 at its reaction center. 
B) is reduced by NADPH. 
C) passes electrons to photosystem I. 
D) does not have a reaction center. 
E) releases CO2 as a by-product.
A

C) passes electrons to photosystem I.

46
Q

Photophosphorylation differs from oxidative phosphorylation in that
A) it involves an electron transport chain.
B) energy is stored in the form of a proton concentration difference.
C) regeneration of ATP is driven by a flow of protons through an ATP synthase.
D) the final electron acceptor is NADP+ and not oxygen.
E) its enzymes are membrane-bound

A

D) the final electron acceptor is NADP+ and not oxygen

47
Q
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) electrons . . . stroma . . . H+ 
E) H+ . . . stroma . . . ATP
A

C) H+ . . . stroma . . . H+

48
Q
A concentration gradient is a form of 
A) kinetic energy. 
B) life. 
C) an exergonic reaction. 
D) potential energy. 
E) entropy
A

D) potential energy

49
Q

) The chloroplast ATP synthase
A) is a nucleic acid complex.
B) transports H+ ions from the stroma to the thylakoid space.
C) couples the flow of H+ to the phosphorylation of NADP+.
D) is embedded in the inner membrane of the chloroplast.
E) helps transport H+ against the concentration gradient.

A

B) transports H+ ions from the stroma to the thylakoid space.

50
Q

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

A

B) is analogous to the production of ATP in mitochondria.

51
Q
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) nuclear . . . light . . . food 
E) food . . . light . . . nuclear
A

A) chemical . . . food . . . light

52
Q
Photosynthetic organisms derive their carbon from 
A) carbon monoxide. 
B) carbon dioxide. 
C) hydrocarbons. 
D) methane. 
E) ribose.
A

B) carbon dioxide.

53
Q

ATP and NADPH
A) play a role in glucose synthesis by plants.
B) are products of the Calvin cycle.
C) are inputs to the photosystems.
D) production is associated with events taking place on the inner mitochondrial membrane.
E) are used in the electron transport chain to pump H+ into the thylakoid space

A

A) play a role in glucose synthesis by plants.

54
Q
To produce one glucose, the Calvin cycle needs to be run through \_\_\_\_\_\_\_\_ time(s). 
A) one 
B) two 
C) four 
D) six 
E) eight
A

D) six

55
Q
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) NADPH 
E) carbon dioxide
A

A) G3P

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

C) photosynthesis.

57
Q

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

A

E) a fuel for cellular respiration and a starting material for making other organic molecules.

58
Q

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.
E) have chloroplasts and vestigial mitochondria.

A

D) have mitochondria and chloroplasts.

59
Q
The addition of oxygen to RuBP by rubisco to form a two-carbon product that is then broken down by the cell to carbon dioxide and water defines 
A) cellular respiration. 
B) photorespiration. 
C) chemiosmosis. 
D) photophosphorylation. 
E) aerobic respiration
A

B) photorespiration.

60
Q

Photorespiration
A) is an evolutionary relic from when atmospheric O2 levels were low and did not interfere with rubisco.
B) is of benefit to the plant since it breaks down rubisco.
C) is attributable to high CO2 levels.
D) produces glucose.
E) produces ATP

A

A) is an evolutionary relic from when atmospheric O2 levels were low and did not interfere with rubisco.

61
Q

61) What is the main adaptive advantage of the C4 and CAM photosynthesis strategies over the C3 strategy?
A) They help the plant conserve water and synthesize glucose efficiently under hot, dry conditions.
B) They allow the plant to fix carbon more efficiently under conditions of low atmospheric CO2.
C) They allow the plant to fix carbon more efficiently in dim or cool conditions.
D) They make it possible for the plant to use the Calvin cycle at night.
E) They allow the plant to avoid photorespiration by producing a four-carbon sugar in place of glucose.

A

A) They help the plant conserve water and synthesize glucose efficiently under hot, dry conditions.

62
Q

62) The greenhouse effect is
A) reduced 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) reduced by the addition of carbon dioxide to the atmosphere, since carbon dioxide removes excess heat from the
Earth’s surface and reflects it back into space.
E) of little concern, since it is part of the normal cycle for the planet.

A

A) reduced by photosynthesis, which removes carbon dioxide from the atmosphere.

63
Q

63) 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 is inversely related to increasing levels of atmospheric CO2.
D) The greenhouse effect will decrease the average temperature of the planet.
E) The greenhouse effect has no direct relationship with the Industrial Revolution of the 1800s.

A

B) The greenhouse effect is exacerbated by the use of fossil fuels.

64
Q

64) 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.
E) Young trees emit ozone-destroying gases at a higher rate than old trees and would thus worsen the ozone-hole
problem while alleviating global warming.

A

C) Most of the biomass of the cut trees would be added to the atmosphere as CO2 within a few years.

65
Q

65) Ozone
A) formation is promoted by CFCs.
B) is broken down by carbon dioxide.
C) is a source of oxygen for cellular respiration.
D) levels in the atmosphere have been steadily increasing in the past century.
E) protects Earth from UV radiation.

A

E) protects Earth from UV radiation.

66
Q
66) Ozone consists of \_\_\_\_\_\_\_\_ oxygen atom(s). 
A) zero 
B) one 
C) two 
D) three 
E) four
A

D) three

67
Q
67) Which of the following has been a major source of ozone destruction over the past 50 years? 
A) chlorofluorocarbons 
B) ethylene glycol 
C) carbon dioxide 
D) chemiosmosis 
E) cellular respiration
A

A) chlorofluorocarbons

68
Q

You’re conducting an experiment to determine the effect of different wavelengths of light on the absorption of carbon dioxide as an indicator of the rate of photosynthesis in aquatic ecosystems. If the rate of photosynthesis increases, the amount of carbon dioxide in the environment will decrease and vice versa. You’ve added an indicator to each solution. When the carbon dioxide concentration decreases, the color of the indicator solution also changes.

Small aquatic plants are placed into three containers of water mixed with carbon dioxide and indicator solution. Container A is placed under normal sunlight, B under green light, and C under red light. The containers are observed for a 24-hour period.
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 both the green light and normal sunlight.
C) absorb the same amount of CO2 as the plants under the green light.
D) absorb less CO2 than the plants under green light.
E) absorb more CO2 than the plants under the green light.

Answer: E
Topic: 7.6
Skill: Application

A

E) absorb more CO2 than the plants under the green light.

69
Q

You’re conducting an experiment to determine the effect of different wavelengths of light on the absorption of carbon dioxide as an indicator of the rate of photosynthesis in aquatic ecosystems. If the rate of photosynthesis increases, the amount of carbon dioxide in the environment will decrease and vice versa. You’ve added an indicator to each solution. When the carbon dioxide concentration decreases, the color of the indicator solution also changes.

Small aquatic plants are placed into three containers of water mixed with carbon dioxide and indicator solution. Container A is placed under normal sunlight, B under green light, and C under red light. The containers are observed for a 24-hour period.

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.
E) CO2 energizes electrons in the electron transport system.

A

A) CO2 is needed to produce sugars in the Calvin cycle.