Deck 7: Capturing Solar Energy: Photosynthesis

Question 1

Before photosynthesis evolved, was rare in Earth?s atmosphere.

A) N₂
B) air
C) O₂
D) CO₂
E) H₂O

Answer 1

O₂

Question 2

The cellular organelle that utilizes sunlight to convert carbon dioxide and water into sugar and oxygen is the

A) mitochondrion.
B) endoplasmic reticulum.
C) chloroplast.
D) thylakoid.
E) cristae.

Answer 2

C

Question 3

Which of the following statements is TRUE regarding the light reactions?

A) They rely on energy provided by glucose synthesis.
B) Oxygen is required.
C) Without water, the system would shut down.
D) Without photosystem I, photosystem II could not occur.
E) ATP and NADPH are needed.

Answer 3

C

Question 4

What structural feature of a leaf enables it to obtain CO₂ from the air?

A) Mesophyll
B) Stomata
C) Chloroplast
D) Epidermis
E) Cuticle

Question 5

All of the following factors influence the rate of photosynthesis EXCEPT

A) light intensity.
B) temperature.
C) atmospheric CO₂ levels.
D) atmospheric N₂ levels.
E) water availability.

Question 6

Carotenoid pigments are found in the

A) mitochondria.
B) stroma of the chloroplasts.
C) nucleus.
D) thylakoid membranes of the chloroplasts.

Question 7

Imagine that a plant in your garden doesnʹt receive an adequate amount of water. Which of the following would be most affected by this?

A) Both the light reactions and the Calvin cycle of photosynthesis
B) The light reactions of photosynthesis only
C) The Calvin cycle of photosynthesis only
D) Neither the light reactions nor the Calvin cycle of photosynthesis

Question 8

All of the following compounds are necessary components for photosynthesis EXCEPT

A) ATP.
B) water.
C) oxygen.
D) carbon dioxide.
E) NADP.

Question 9

A pigment that absorbs red and blue light and reflects green light is

A) phycocyanin.
B) melanin.
C) carotenoid.
D) xanthophyll.
E) chlorophyll.

Question 10

The energy required for photosynthesis to occur is

A) oxygen.
B) ultraviolet light.
C) visible light.
D) air.
E) glucose.

Question 11

Specifically, molecules of chlorophyll are located in the membranes of sacs called

A) thylakoids.
B) stroma.
C) grana.
D) stoma.
E) vesicles.

Question 12

Suppose that you are experimenting with different types of lighting for your indoor green plants. Which of the following colors of light will be most effective?

A) Red and green
B) Black
C) Red and blue
D) Green
E) Orange and yellow

Question 13

Albino corn has no chlorophyll. You would expect albino corn seedlings to

A) capture light energy in the white end of the visible light spectrum.
B) use accessory pigments such as carotenoids to capture light.
C) fail to thrive because they cannot capture light energy.
D) synthesize glucose indefinitely, using stored ATP and NADPH.
E) switch from the C4 pathway to the crassulacean acid metabolism (CAM) pathway.

Question 14

Which of the following is NOT true of chlorophyll?

A) It absorbs light at the red and blue ends of the spectrum.
B) It is found in the thylakoid membrane.
C) It is found in mitochondria.
D) It reflects green wavelengths of light.
E) It is the main photosynthetic pigment in plants.

Question 15

Pigments that absorb light energy to drive photosynthesis include

A) anthocyanins only.
B) chlorophyll only.
C) carotenoids only.
D) chlorophyll and carotenoids.
E) carotenoids and anthocyanins.

Question 16

The replacement electrons for the reaction center of photosystem II come from

A) O₂.
B) H₂O.
C) glucose.
D) photosystem I.
E) NADPH.

Question 17

The products of photosynthesis are

A) glucose and carbon dioxide.
B) glucose, water, and oxygen.
C) carbon dioxide, chlorophyll, and oxygen.
D) carbon dioxide, water, and energy.
E) glucose and water.

Question 18

The vast majority of chloroplasts found in a leaf are in the

A) stroma.
B) cuticle.
C) vascular bundles.
D) epidermis.
E) mesophyll.

Question 19

Imagine that a scientist discovers a mutant plant seedling that appears to lack stomata. What would be the effect of this?

A) Glucose would not be able to enter the plant as a reactant for photosynthesis.
B) Visible wavelengths of light would be unable to reach the chloroplasts.
C) CO₂ would not be able to enter the plant as a reactant for photosynthesis.
D) Additional ATP would be produced by the seedling, and the plant would grow taller.

Question 20

In the chloroplast, energy in sunlight is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule that can transfer energy in sunlight to an energized electron. This chlorophyll molecule is called the

A) reaction center.
B) photoelectric point.
C) accessory pigment.
D) nucleus.
E) electron-carrier molecule.

Question 21

Which of the following is a source of electrons that plants use for reduction reactions during photosynthesis?

A) H₂O
B) RuBP
C) Glucose
D) O₂
E) CO₂

Question 22

The ATP and NADPH synthesized during the light reactions are

A) transported to the mitochondria.
B) pumped into a compartment within the thylakoid membrane.
C) transported into the nucleus.
D) moved to the stroma.
E) dissolved in the cytoplasm.

Question 23

What is produced in the electron transport system associated with photosystem II?

A) CO₂
B) Glucose
C) ATP
D) NADPH
E) O₂

Question 24

The energy of the movement of electrons down a concentration gradient via electron transport within chloroplasts and mitochondria is used to generate

A) ATP.
B) CO_2.
C) H₂O.
D) glucose.
E) O₂.

Question 25

From where does the O2 released during the light reactions of photosynthesis come?

A) RuBP
B) ATP
C) CO₂
D) C₆H₁₂O₆
E) H₂O

Question 26

The role of water in photosynthesis is to

A) maintain turgor pressure.
B) provide oxygen.
C) provide electrons.
D) provide H₂.

Question 27

The light reactions of photosynthesis result in which of the following?

A) Oxidation of CO₂
B) Reduction of H₂O
C) Oxidation of glucose
D) Production of ATP
E) Oxidation of chlorophyll

Question 28

The NADPH required for carbon dioxide fixation during the Calvin cycle is formed

A) by the hydrolysis of ATP.
B) by the reduction of oxygen.
C) only in C₄ plants.
D) during the light reactions.
E) in the mitochondria.

Question 29

Which process of photosynthesis is directly linked to the production of ATP?

A) Photosystem II
B) Splitting of a water molecule
C) Generation of NADPH
D) Fixing of carbon
E) Synthesis of O₂

Question 30

Which sequence accurately describes the flow of electrons in photosynthesis?

A) Photosystem II ? photosystem I ? NADP ? H₂O
B) H₂O ? photosystem I ? photosystem II ? NADP
C) H₂O ? photosystem II ? photosystem I ? NADP
D) Photosystem I ? photosystem II ? NADP ? H2O
E) Photosystem I ? photosystem II ? H₂O ? NADP

Question 31

Hydrogen ions cross the thylakoid membranes from the stroma by

A) facilitated diffusion.
B) simple diffusion.
C) active transport.
D) synthesis.
E) osmosis.

Question 32

You are carrying out an experiment on several aquatic plants in your fish tank. You decide to expose two of the plants to green light and two to blue light. You want to determine which type of light is best for the light reactions, so to reach your conclusions, you decide to record the amount of oxygen bubbles produced. Which of the following results would be expected?

A) There would be more bubbles from the plants in green light than from those in blue light.
B) There would be the same number of bubbles from plants in blue or green light.
C) There would be more bubbles from the plants in blue light than from those in green light.
D) No bubbles would be produced in either green light or blue light.

Question 33

The energy of the movement of electrons down a concentration gradient via electron transport within the thylakoid membrane is used to generate

A) glucose.
B) ATP.
C) CO₂.
D) O₂.
E) H₂O.

Question 34

Light reactions produce

A) glucose, ATP, and O₂.
B) ATP, NADPH, and CO₂.
C) ATP, NADPH, and H₂O.
D) glucose, ATP, and CO₂.
E) ATP, NADPH, and O₂.

Question 35

Which of the following statements is TRUE about the light reactions?

A) ATP is the final electron acceptor.
B) Photosystem II generates ATP, whereas photosystem I generates NADPH.
C) Photosystem I generates ATP, whereas photosystem II generates NADPH.
D) NADPH and ATP are both synthesized from the light reactions within photosystem I.

Question 36

Suppose you are studying photosynthesis in a research lab. You grow your plants in a chamber with a source of water that has a radioactively labeled oxygen atom. What photosynthetic product will be radioactive?

A) O₂ gas
B) CO₂ gas
C) ATP
D) Glucose
E) NADPH

Question 37

Which of the following provides O₂ as an end product?

A) Glycolysis
B) Synthesis
C) Light-independent reactions
D) Light reactions
E) Cellular respiration

Question 38

Which of the following statements about the light reactions of photosynthesis is FALSE?

A) The splitting of water molecules provides a source of electrons.
B) NADPH becomes oxidized to NADP⁺.
C) An electron transport chain is used to create a proton gradient.
D) Chlorophyll (and other pigments) absorbs light energy, which excites electrons.
E) ATP is formed.

Question 39

The primary function of the light reactions of photosynthesis is to

A) produce NADPH used in respiration.
B) produce energy-rich glucose from carbon dioxide and water.
C) convert light energy to the chemical energy of lipids.
D) use ATP to make glucose.
E) produce energy-rich ATP and NADPH.

Question 40

During the process of photosynthesis, solar energy is converted to

A) mechanical energy.
B) thermal energy.
C) chemical energy.
D) nuclear energy.
E) heat energy.

Question 41

In the reduction of CO₂ during C₄ photosynthesis, which of the following initially combines with CO₂?

A) PEP
B) RuBP
C) PGAL
D) NADH
E) PGA

Question 42

What is the correct order for the reactions of the Calvin cycle?

A) Carbon fixation, synthesis of G3P, regeneration of RuBP
B) Carbon fixation, regeneration of RuBP, synthesis of G3P
C) Synthesis of G3P, regeneration of RuBP, carbon fixation
D) Synthesis of G3P, carbon fixation, regeneration of RuBP
E) Regeneration of RuBP, carbon fixation, synthesis of G3P

Question 43

The term cycle is used to describe the Calvin cycle because

A) the reactions occur only once in a 24-hour period.
B) glucose is synthesized during the process.
C) the process depends on products from the light reactions.
D) the metabolic pathway begins and ends with RuBP.
E) CO2 is fixed.

Question 44

What kind of habitat does a C₄-pathway plant favor?

A) Cool and dry
B) Wet and cloudy
C) Totally aquatic
D) Cool and moist
E) Hot and dry

Question 45

What condition(s) must be met for glucose to be produced during photosynthesis?

A) The concentration of O₂ must be significantly higher than that of CO₂.
B) Mitochondria must convert light energy to ATP.
C) The products of light-dependent reactions must be available.
D) NADH and FADH are available.

Question 46

Which of the following occurs during the Calvin cycle of photosynthesis?

A) Nothing occurs because the plant rests in the dark.
B) Carbon dioxide is converted to chemicals that can be used to make sugars.
C) Water is converted to its most basic elements, hydrogen and water.
D) Chlorophyll acts as an enzyme, but only in the dark.

Question 47

Where is glucose synthesized during photosynthesis?

A) Membrane proteins
B) Stroma
C) Cytoplasm
D) Thylakoids
E) Matrix

Question 48

Photorespiration is detrimental for a plant because

A) CO₂ is synthesized.
B) no glucose is produced.
C) glucose is synthesized.
D) O₂ is required.
E) RuBP is degraded.

Question 49

During photosynthesis, when is CO₂ utilized?

A) During the light reactions only
B) During the Calvin cycle only
C) During both the light reactions and the Calvin cycle
D) During neither the light reactions nor the Calvin cycle

Question 50

In the C₄ pathway, what is the source of carbon?

A) NADPH
B) Glucose
C) Water
D) ATP
E) Carbon dioxide

Question 51

NADPH is a reactant required during which of the following reactions?

A) The light reactions only
B) The Calvin cycle only
C) Both the light reactions and the Calvin cycle
D) Neither the light reactions nor the Calvin cycle

Question 52

Glucose is made during which of the following reactions?

A) The light reactions only
B) The Calvin cycle only
C) Both the light reactions and the Calvin cycle
D) Neither the light reactions nor the Calvin cycle

Question 53

What happens to CO₂ when it moves into the stroma?

A) It immediately passes on to the thylakoids.
B) The CO₂ becomes a by-product of cellular respiration.
C) The CO₂ splits into C and O₂.
D) It is converted to water.
E) It gets incorporated into the Calvin cycle and goes toward the formation of glucose.

Question 54

All of the following are part of the Calvin cycle EXCEPT

A) generation of ATP.
B) synthesis of G3P.
C) regeneration of RuBP.
D) carbon fixation.

Question 55

Where do the reactions of a C₄ pathway occur in a plant such as corn?

A) Mesophyll cells only
B) Epidermal cells only
C) Bundle sheath cells only
D) Mesophyll and bundle sheath cells
E) Bundle sheath and epidermal cells

Question 56

Enzymes are required during which of the following reactions?

A) The light reactions only
B) The Calvin cycle only
C) Both the light reactions and the Calvin cycle
D) Neither the light reactions nor the Calvin cycle

Question 57

NADPH is synthesized during which of the following reactions?

A) The light reactions only
B) The Calvin cycle only
C) Both the light reactions and the Calvin cycle
D) Neither the light reactions nor the Calvin cycle

Question 58

In the C₃ pathway, where does the carbon come from to form glucose?

A) Enzymes
B) ATP and NADPH
C) Chlorophyll
D) Water
E) Atmospheric CO₂

Question 59

Water is required to drive which of the following reactions?

A) The light reactions only
B) The Calvin cycle only
C) Both the light reactions and the Calvin cycle
D) Neither the light reactions nor the Calvin cycle

Question 60

In green plants, the primary function of the Calvin cycle is to

A) split water and release oxygen.
B) transport glucose out of the chloroplast.
C) use ATP to release carbon dioxide.
D) construct the building blocks of simple sugars from carbon dioxide.
E) use NADPH to release carbon dioxide.

Question 61

The cells in the _________layer of the leaf contain the majority of a leaf?s chloroplasts.

Question 62

Light-harvesting pigments in the chloroplast include chlorophyll and the yellowish accessory pigments called _________.

Question 63

The carotenoids and other accessory pigments in the chloroplast help capture light into the reaction centerʹs chlorophyll molecules.

Question 64

Carbon dioxide is required in the light reactions of photosynthesis.

Question 65

All of the following are true of biofuels EXCEPT

A) the goal of their use is to reduce harmful carbon dioxide emissions.
B) demand for biofuels has placed demands on rain-forest lands.
C) there is concern that using food products as a fuel source will reduce the global food supply and increase food prices.
D) biofuels are the only solution to our growing need for fuels in the future.
E) these are fuels such as methane produced from renewable biological resources such as soybeans and corn.

Question 66

_________is the main light-capturing molecule in chloroplasts and is responsible for giving leaves their characteristic green color.

Question 67

The stacked grana are disk-shaped, interconnected membranous sacs embedded in the membrane of the stroma.

Question 68

In C₄ photosynthesis, where does the carbon in newly synthesized glucose come from?

A) Water
B) Atmospheric CO₂
C) Chlorophyll
D) Enzymes
E) ATP and NADPH

Question 69

C₃ plants are adapted to__________environmental conditions, whereas C₄ plants are adapted to __________conditions.

A) dry; wet
B) temperate; cool and rainy
C) drought; rainy
D) wet; dry
E) high-light; low-light

Question 70

During the light reactions of photosynthesis, the synthesis of_________ is coupled to the diffusion of protons.

Question 71

In C₃ photosynthesis, what fixes the carbon?

A) PGAL
B) ATP
C) RuBP
D) PGA
E) PEP

Question 72

Many plants have evolved leaves that have adjustable pores, called_________ , which allow for gas exchange and water loss.

Question 73

Where does the C₄ cycle get its name?

A) The first product in the cycle has four carbons.
B) Four CO₂ molecules are released.
C) It is a four-step process.
D) Only four carbons are used in the cycle.
E) PEP is a four-carbon molecule.

Question 74

The photosystems are involved in the light reactions of photosynthesis.

Question 75

Light reactions occur in the_________ , and the Calvin cycle occurs in the_________ of the chloroplast of a typical mesophyll leaf cell.

Question 76

The majority of the leafʹs chloroplasts are found in the mesophyll cells.

Question 77

The process of photosynthesis converts solar energy to_________ energy stored in the bonds of glucose.

Question 78

In the process of photosynthesis, _________and_________formed during the light reactions are required in the Calvin cycle to reduce carbon dioxide to glucose.

Question 79

If C₄ photosynthesis prevents photorespiration, why haven?t all plants evolved to use the C₄ pathway?

A) All plants will evolve to be C₄ in time.
B) C₄ produces some toxic by-products.
C) Only some plants use C₄ photosynthesis.
D) C₄ is not advantageous in all climates.
E) C₄ is advantageous only in high-oxygen habitats.

Question 80

Under dry conditions, a C₄ plant is more efficient at photosynthesis than that of a C₃ plant.