Question 1

During CO2 fixation, CO2 combines with

Accepted Answer

A)  NADPH. 
B)  3PG. 
C)  G3P. 
D)  Ribulose 1,5-bisphosphate (RuBP). 
E)  water. 
A)  NADPH. 
B)  3PG. 
C)  G3P. 
D)  Ribulose 1,5-bisphosphate (RuBP). 
E)  water.

Question 2

The molecule(s) representing the net energy output of one cycle of photosynthetic cyclic electron transport is/are

Accepted Answer

A)  ATP. 
B)  ATP and NAD+. 
C)  NADPH. 
D)  ATP and NADPH. 
E)  sugar. 
A)  ATP. 
B)  ATP and NAD+. 
C)  NADPH. 
D)  ATP and NADPH. 
E)  sugar.

Question 3

Photosystem I (PSI) and photosystem II (PSII) have similarities and differences.Which statement comparing these two systems is false?

Accepted Answer

A)  PSI and PSII have reaction center chlorophylls that absorb light at different wavelengths. 
B)  Both PSI and PSII reaction centers draw electrons from electron donors after they are excited by photons and oxidized. 
C)  The excited chlorophyll (Chl*) of a PSII reaction center loses an electron and is re-reduced by water, while the Chl* of a PSI reaction center passes its electrons via intermediates to NADP+. 
D)  The energy trapped in the excited states of both PSI and PSII is used to reduce NADP+. 
E)  PSII and PSI are both located in the thylakoid membrane along with the electron transport chain. 
A)  PSI and PSII have reaction center chlorophylls that absorb light at different wavelengths. 
B)  Both PSI and PSII reaction centers draw electrons from electron donors after they are excited by photons and oxidized. 
C)  The excited chlorophyll (Chl*) of a PSII reaction center loses an electron and is re-reduced by water, while the Chl* of a PSI reaction center passes its electrons via intermediates to NADP+. 
D)  The energy trapped in the excited states of both PSI and PSII is used to reduce NADP+. 
E)  PSII and PSI are both located in the thylakoid membrane along with the electron transport chain.

Question 4

The equation below describes a photosynthetic reaction. 12 H2S + 6 CO2 + light F1F1F1S1F1F1F10 C6H12O6 + 12 S + 6 H2O
This reaction

Accepted Answer

A)  uses H2O as an electron donor. 
B)  uses H2S as an electron donor. 
C)  is found in plants. 
D)  produces fatty acids. 
E)  does not involve water. 
A)  uses H2O as an electron donor. 
B)  uses H2S as an electron donor. 
C)  is found in plants. 
D)  produces fatty acids. 
E)  does not involve water.

Question 5

In noncyclic photophosphorylation, electrons flow in a one-way path from water to

Accepted Answer

A)  ATP. 
B)  O2. 
C)  NADP+. 
D)  CO2. 
E)  sugar. 
A)  ATP. 
B)  O2. 
C)  NADP+. 
D)  CO2. 
E)  sugar.

Question 6

When white light strikes a blue pigment, blue light is

Accepted Answer

A)  reduced. 
B)  absorbed. 
C)  converted to chemical energy. 
D)  reflected. 
E)  used to synthesize ATP. 
A)  reduced. 
B)  absorbed. 
C)  converted to chemical energy. 
D)  reflected. 
E)  used to synthesize ATP.

Question 7

Succulents, pineapples, and many cacti are which type of plants?

Accepted Answer

A)  CAM 
B)  C3 
C)  C4 
D)  Plants that undergo photorespiration 
E)  Plants that undergo cellular respiration 
A)  CAM 
B)  C3 
C)  C4 
D)  Plants that undergo photorespiration 
E)  Plants that undergo cellular respiration

Question 8

Corn, Bermuda grass, and sugarcane are examples of

Accepted Answer

A)  CAM plants. 
B)  C3 plants. 
C)  C4 plants. 
D)  succulents. 
E)  desert plants. 
A)  CAM plants. 
B)  C3 plants. 
C)  C4 plants. 
D)  succulents. 
E)  desert plants.

Question 9

Refer to the table below.   A biologist is measuring the uptake of carbon dioxide in both C4 and CAM plants.The data in the table were collected during one of the experiments conducted by this biologist and are consistent with the uptake of carbon dioxide in _______ plants.

Accepted Answer

Question 10

Refer to the figure below.   This image represents a C4 plant, which carries out an initial carbon-fixation step using PEP carboxylase in its mesophyll and then transfers the product to its bundle sheath cells, where it is decarboxylated, providing a ready and concentrated source of carbon dioxide to the chloroplasts in these cells.The starch grains in the bundle sheath cells result from an accumulation of _______ molecules produced from active and continuing photosynthesis taking place in these cells.

Accepted Answer

glyceralde

Question 11

The light reactions

Accepted Answer

A)  require light of any wavelength. 
B)  result in the hydrolysis of ATP. 
C)  produce NADPH used in the Calvin cycle. 
D)  occur in C4 plants only. 
E)  take place in the stroma. 
A)  require light of any wavelength. 
B)  result in the hydrolysis of ATP. 
C)  produce NADPH used in the Calvin cycle. 
D)  occur in C4 plants only. 
E)  take place in the stroma.

Question 12

In addition to driving the synthesis of ATP and the reduction of NADP+ to NADPH, light stimulates the Calvin cycle by _______ and _______.

Accepted Answer

A)  decreasing the pH of the stroma; reduction of some Calvin cycle enzymes 
B)  increasing the pH of the stroma; reduction of some Calvin cycle enzymes 
C)  increasing the pH of the stroma; oxidation of some Calvin cycle enzymes 
D)  decreasing the pH of the stroma; oxidation of some Calvin cycle enzymes 
E)  increasing the pH of the thylakoid lumen; reduction of some Calvin cycle enzymes 
A)  decreasing the pH of the stroma; reduction of some Calvin cycle enzymes 
B)  increasing the pH of the stroma; reduction of some Calvin cycle enzymes 
C)  increasing the pH of the stroma; oxidation of some Calvin cycle enzymes 
D)  decreasing the pH of the stroma; oxidation of some Calvin cycle enzymes 
E)  increasing the pH of the thylakoid lumen; reduction of some Calvin cycle enzymes

Question 13

Refer to the figure below.   The figure illustrates the locations and movements of materials in and out of a chloroplast in a plant cell.How would you complete this diagram by filling in the names of the molecules corresponding to boxes X and Z?

Accepted Answer

A)  X = sucrose; Z = starch 
B)  X = glucose; Z = starch 
C)  X = starch; Z = sucrose 
D)  X = sucrose; Z = fructose 
E)  X = fructose; Z = glucose 
A)  X = sucrose; Z = starch 
B)  X = glucose; Z = starch 
C)  X = starch; Z = sucrose 
D)  X = sucrose; Z = fructose 
E)  X = fructose; Z = glucose

Question 14

Researchers developing herbicidal chemical agents tested one, compound Q, on the ability of chloroplasts isolated from spinach leaves to carry out three stages of photosynthesis under illumination.The results are shown in the table below.   The table indicates the levels of activity in these photosynthesis stages.The number of "+" signs indicates the relative level of activity, while "0" indicates no activity.Which statement is consistent with these results?

Accepted Answer

A)  Compound Q binds to one of the electron carrier proteins in photosystem I and inhibits its ability to accept electrons. 
B)  Compound Q inhibits NADP+ reductase, the enzyme that catalyzes the transfer of electrons in the formation of NADPH. 
C)  Compound Q induces the light reactions and light-independent reactions to lose their dependency on light. 
D)  Compound Q reverses the sequence of the light reactions and light-independent reactions. 
E)  Compound Q allows protons to leak through the thylakoid membrane, disrupting the ability of the chloroplast to synthesize ATP required by the Calvin cycle. 
A)  Compound Q binds to one of the electron carrier proteins in photosystem I and inhibits its ability to accept electrons. 
B)  Compound Q inhibits NADP+ reductase, the enzyme that catalyzes the transfer of electrons in the formation of NADPH. 
C)  Compound Q induces the light reactions and light-independent reactions to lose their dependency on light. 
D)  Compound Q reverses the sequence of the light reactions and light-independent reactions. 
E)  Compound Q allows protons to leak through the thylakoid membrane, disrupting the ability of the chloroplast to synthesize ATP required by the Calvin cycle.

Question 15

In the following equation: 12 H2O F1F1F1S1F1F1F10 24 H+ + 24 e- + 6 O2

Accepted Answer

A)  oxygen atoms are oxidized. 
B)  water is oxidized. 
C)  oxygen ions are produced. 
D)  water is reduced. 
E)  electrons are gained by water. 
A)  oxygen atoms are oxidized. 
B)  water is oxidized. 
C)  oxygen ions are produced. 
D)  water is reduced. 
E)  electrons are gained by water.

Question 16

The precise moment when light energy is transformed into chemical energy is the point at which

Accepted Answer

A)  light shines on chlorophyll. 
B)  water is hydrolyzed. 
C)  the P680 chlorophylls are oxidized. 
D)  chlorophyll is reduced. 
E)  the CO2 from air is captured in a sugar. 
A)  light shines on chlorophyll. 
B)  water is hydrolyzed. 
C)  the P680 chlorophylls are oxidized. 
D)  chlorophyll is reduced. 
E)  the CO2 from air is captured in a sugar.

Question 17

Refer to the table below showing results of some researchers who exposed wheat plants to 14C-labeled carbon dioxide for various lengths of time in the light before extracting various compounds from leaves.The extracted compounds were separated using paper chromatography, and the amount of radioactivity for each spot on the chromatogram was measured for a specified duration of light exposure.The results for sucrose are shown in the table.   In a control run, during which plants were kept in the dark, no radioactivity was incorporated into sucrose over a 25-hour time period.Which statement about sucrose is supported by these data?

Accepted Answer

A)  A plant can use sucrose as a source of energy during periods of darkness when photosynthesis shuts down. 
B)  Sucrose is the form of fixed carbon that is transported from photosynthetic tissues to nonphotosynthetic tissues throughout the plant. 
C)  G3P formed via the Calvin cycle can enter gluconeogenesis to form hexose phosphates and then sucrose in plant leaves. 
D)  Glucose and fructose are monosaccharides that bond together to form the disaccharide sucrose. 
E)  Sucrose serves as a source of fixed carbon that can be distributed throughout the plant. 
A)  A plant can use sucrose as a source of energy during periods of darkness when photosynthesis shuts down. 
B)  Sucrose is the form of fixed carbon that is transported from photosynthetic tissues to nonphotosynthetic tissues throughout the plant. 
C)  G3P formed via the Calvin cycle can enter gluconeogenesis to form hexose phosphates and then sucrose in plant leaves. 
D)  Glucose and fructose are monosaccharides that bond together to form the disaccharide sucrose. 
E)  Sucrose serves as a source of fixed carbon that can be distributed throughout the plant.

Question 18

Refer to the figure below.   Which set of molecules belong in the lettered boxes?

Accepted Answer

A)  A = NADP+; B = ATP; C = NADPH; D = ADP + Pi 
B)  A = ATP; B = ADP + Pi; C =NADPH; D = NADP+ 
C)  A = NADPH; B = ADP + Pi; C = NADP+; D = ATP 
D)  A = ATP; B = ADP + Pi; C = NADP+; D = NADPH 
E)  A = NADP+; B = ADP + Pi; C = NADPH; D = ATP 
A)  A = NADP+; B = ATP; C = NADPH; D = ADP + Pi 
B)  A = ATP; B = ADP + Pi; C =NADPH; D = NADP+ 
C)  A = NADPH; B = ADP + Pi; C = NADP+; D = ATP 
D)  A = ATP; B = ADP + Pi; C = NADP+; D = NADPH 
E)  A = NADP+; B = ADP + Pi; C = NADPH; D = ATP

Question 19

Which statement about the light-independent reactions of photosynthesis is false?

Accepted Answer

A)  The term "light-independent reactions" refers to the pathways by which CO2 is reduced to carbohydrates. 
B)  Light-independent reactions take place in the chloroplast stroma. 
C)  ATP is consumed by light-independent reactions. 
D)  NADPH is consumed by light-independent reactions. 
E)  Light-independent reactions operate in the dark. 
A)  The term "light-independent reactions" refers to the pathways by which CO2 is reduced to carbohydrates. 
B)  Light-independent reactions take place in the chloroplast stroma. 
C)  ATP is consumed by light-independent reactions. 
D)  NADPH is consumed by light-independent reactions. 
E)  Light-independent reactions operate in the dark.

Question 20

Water molecules labeled with 18O were added to the water given to a plant and subsequently taken up by the plant's roots.If molecule(s) associated with the plant were analyzed at a later time, which would you expect to contain 18O?

Accepted Answer

A)  Water 
B)  Oxygen 
C)  Carbon dioxide 
D)  Carbohydrate 
E)  Lipid 
A)  Water 
B)  Oxygen 
C)  Carbon dioxide 
D)  Carbohydrate 
E)  Lipid

Exam 10: Photosynthesis: Energy From Sunlight

During CO2 fixation, CO2 combines with

The molecule(s) representing the net energy output of one cycle of photosynthetic cyclic electron transport is/are

Photosystem I (PSI) and photosystem II (PSII) have similarities and differences.Which statement comparing these two systems is false?

The equation below describes a photosynthetic reaction. 12 H2S + 6 CO2 + light  C6H12O6 + 12 S + 6 H2O This reaction

In noncyclic photophosphorylation, electrons flow in a one-way path from water to

When white light strikes a blue pigment, blue light is

Succulents, pineapples, and many cacti are which type of plants?

Corn, Bermuda grass, and sugarcane are examples of

Refer to the table below. A biologist is measuring the uptake of carbon dioxide in both C4 and CAM plants.The data in the table were collected during one of the experiments conducted by this biologist and are consistent with the uptake of carbon dioxide in _______ plants.

The light reactions

In addition to driving the synthesis of ATP and the reduction of NADP+ to NADPH, light stimulates the Calvin cycle by _______ and _______.

Refer to the figure below. The figure illustrates the locations and movements of materials in and out of a chloroplast in a plant cell.How would you complete this diagram by filling in the names of the molecules corresponding to boxes X and Z?

In the following equation: 12 H2O  24 H+ + 24 e- + 6 O2

The precise moment when light energy is transformed into chemical energy is the point at which

Refer to the figure below. Which set of molecules belong in the lettered boxes?

Which statement about the light-independent reactions of photosynthesis is false?

Water molecules labeled with 18O were added to the water given to a plant and subsequently taken up by the plant's roots.If molecule(s) associated with the plant were analyzed at a later time, which would you expect to contain 18O?

Studying Life

Small Molecules and the Chemistry of Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Communication and Multicellularity

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

Populations

Species Interactions

Communities

Ecosystems

A Changing Biosphere

Filters

During CO₂ fixation, CO₂ combines with

The equation below describes a photosynthetic reaction. 12 H₂S + 6 CO₂+ light  C₆H₁₂O₆ + 12 S + 6 H₂O This reaction

Refer to the table below. A biologist is measuring the uptake of carbon dioxide in both C₄ and CAM plants.The data in the table were collected during one of the experiments conducted by this biologist and are consistent with the uptake of carbon dioxide in _______ plants.

In addition to driving the synthesis of ATP and the reduction of NADP⁺ to NADPH, light stimulates the Calvin cycle by _ and _.

In the following equation: 12 H₂O  24 H⁺ + 24 e^- + 6 O₂

Water molecules labeled with ¹⁸O were added to the water given to a plant and subsequently taken up by the plant's roots.If molecule(s) associated with the plant were analyzed at a later time, which would you expect to contain ¹⁸O?