Deck 6: Pathways of Photosynthesis

Question 1

Which of the following organisms use organic molecules produced by photosynthesis?

A)Autotrophs only
B)Heterotrophs only
C)Heterotrophs and autotrophs
D)Only plants and algae
E)Only animals

Answer 1

C
Explanation: The organic molecules produced by photosynthesis feed not only the autotrophs which make them (such as plants and algae),but also heterotrophs (such as animals).

Question 2

During the process of photosynthesis,which of the following products are formed?

A)carbohydrate and oxygen
B)carbon dioxide and oxygen
C)carbohydrate and water
D)carbohydrate,water,and carbon dioxide
E)carbohydrate and carbon dioxide

Answer 2

A
Explanation: In photosynthesis,carbon dioxide is converted to carbohydrate,and water is split,releasing oxygen.

Question 3

Which of the following statements,if true,would be a major change to how photosythesis works?

A)They need light to work.
B)They occur on the surface of the thylakoid membrane.
C)They use water and pigment molecules.
D)They occur in the chloroplast.
E)They occur in the stroma of the chloroplast.

Answer 3

E
Explanation: The light reactions of photosynthesis occur in the thylakoid membrane,not in the stroma,of the chloroplast.

Question 4

Flattened sacs within the chloroplast are known as

A)chlorophylls.
B)stomata.
C)thylakoids.
D)stroma.
E)mesophylls.

Question 5

Water is split and oxygen is released during which process in photosynthesis?

A)Electron Transport Chain
B)Cyclic Electron Pathway
C)Calvin Cycle
D)Light Reactions
E)ATP synthesis

Question 6

Why is water split during photosynthesis?

A)To replace the electron lost in photosystem II
B)To replace the electron lost in the first electron acceptor
C)To replace the electron lost in the second electron acceptor
D)To replace the electron lost in photosystem I
E)To replace the electron lost in the electron transport chain

Question 7

Because oxidation and reduction go hand in hand,the entire reaction is called a synthesis reaction.

Question 8

The substance that initially traps solar energy in photosynthesis is

A)chlorophyll.
B)RuBP.
C)water.
D)glucose.
E)pyruvatE.

Question 9

In a study of the raw materials used for photosynthesis,what two kinds of molecules would be studied?

A)glucose and oxygen
B)carbon dioxide and glucose
C)carbon dioxide and water
D)carbon dioxide and oxygen
E)glucose and water

Question 10

The carbon atoms in the carbohydrate produced by photosynthesis come from carbon dioxide.

Question 11

Figure:
This figure shows a plant chloroplast.What does "d" represent?

A)outer chloroplast membrane
B)thylakoid membrane
C)stroma
D)inner chloroplast membrane
E)cuticle

Question 12

What is the significance of the stroma of the chloroplast?

A)It contains metabolic enzymes used to reduce carbon dioxide to carbohydrate.
B)It is where the chlorophyll is stored.
C)It is where oxygen leaves the plant.
D)It helps plants absorb water.
E)It is where carbon dioxide enters the leaf.

Question 13

The reason why most leaves are green is that they absorb the green wavelengths of light.

Question 14

The reason that deciduous leaves turn red and yellow in the fall is

A)Chlorophyll is converted into bright carotenoid pigments.
B)When chlorophyll breaks down,the red and yellow pigments which are already present become visible.
C)It is a chemical reaction involving the formation of ice crystals.
D)Bright pigments are shifted up from the roots while chlorophyll moves down.
E)Red and yellow pigments can only be made when temperatures are cool.

Question 15

What part of the light reactions starts off photosynthesis?

A)Electron Transport Chain
B)Photosystem I
C)Calvin Cycle
D)Photosystem II
E)ATP Synthesis

Question 16

If a molecule has been reduced,which of the following statements must be true?

A)It has lost electrons.
B)The number of electrons in the molecule has stayed the same.
C)It has lost oxygen.
D)It has gained electrons.
E)It has gained oxygen.

Question 17

Figure:
In the figure shown,what does a.represent?

A)oxygen
B)water
C)glucose
D)carbon dioxide
E)ATP

Question 18

Which of the following statements would disqualify an organism as an autotroph?

A)They must take in organic matter to make energy.
B)They produce their own food.
C)They are autotrophs.
D)They convert light energy into chemical energy.
E)Cyanobacteria are autotrophs.

Question 19

Which of the following is reduced as a result of the Calvin cycle?

A)carbon dioxide
B)oxygen
C)light
D)water
E)glucose

Question 20

If the electron transport chain stopped during photosynthesis,what would be the direct result?

A)Water would not be split.
B)The plant could not absorb light.
C)ATP would not be produced.
D)No electrons would be excited in the photosystem.
E)No pigment molecules would be madE.

Question 21

Electrons move from photosystem II to photosystem I via what part of photosynthesis

A)Electron Transport Chain
B)Reaction Center
C)Electron Acceptors
D)Pigment cComplexes
E)Calvin Cycle

Question 22

The major goal of the Calvin cycle is to produce what material?

A)ATP
B)carbohydrate
C)NADPH
D)RuBP
E)NADP⁺

Question 23

What would be the effect of increased oxygen on C₃ plants?

A)increased photosynthetic efficiency
B)increased carbon dioxide uptake
C)switch to C₄ photosynthesis
D)switch to CAM photosynthesis
E)decreased efficiency of photosynthesis

Question 24

The method of turning ADP into ATP is called chemiosmosis because ATP production is tied to a hydrogen ion gradient across a membrane.

Question 25

What would happen if the molecule RuBP disappeared from a plant?

A)The electron transport chain would stop.
B)The plant could no longer split water.
C)The plant could no longer absorb light.
D)Carbon dioxide fixation would stop.
E)Pigment production would stop.

Question 26

The main type of photosynthesis found in plants native to hot,arid climates is

A)C₃.
B)Partitioned.
C)CAM.
D)C₄.
E)Cyclic.

Question 27

The major advantage of the CAM pathway is

A)oxygen conservation.
B)adaptation for wet conditions.
C)adaptation for cool temperatures.
D)that it allows the plant to keep its stomata open during the day.
E)water conservation.

Question 28

What is(are)the end product(s)of the light reactions in photosynthesis?

A)ATP only
B)NADP⁺ and ATP
C)NADP⁺ and ADP
D)NADPH and ADP
E)NADPH and ATP

Question 29

If a student was studying an ecosystem where the temperature and rainfall are moderate,which type of plant would most likely predominate?

A)C₄
B)CIM
C)C₃
D)Mixed CAM/C₃
E)CAM

Question 30

Most major food plants such as wheat,oats,and rice are in the group of

A)nonphotosynthetic plants.
B)C₃ plants.
C)C₄ plants.
D)succulent plants.
E)CAM plants.

Question 31

When carbon dioxide is in limited supply,which of the following types of plants would have the greatest advantage?

A)C₃
B)annual
C)short
D)C₄
E)non-green

Question 32

A biologist is studying the formation of carbohydrate during photosynthesis,so the best part of the chloroplast to study would be what?

A)chloroplast stroma
B)outer chloroplast membrane
C)inner chloroplast membrane
D)thylakoid membrane
E)thylakoid space

Question 33

The last step in the Calvin cycle is

A)carbon dioxide fixation.
B)electron transport.
C)carbon dioxide reduction.
D)chemiosmosis.
E)RuBP regeneration.

Question 34

Which of the following is more true of a C₃ plant rather than of a C₄ plant?

A)They are specialized for environments with moderate temperatures and rainfall.
B)Their mesophyll cells are arranged in parallel rows.
C)They have chloroplasts in their mesophyll and bundle sheath cells.
D)They work efficiently at low levels of carbon dioxide.
E)They work efficiently at low levels of water.

Question 35

In C₄ plants,the Calvin cycle occurs in the bundle sheath cells and not in the mesophyll cells.

Question 36

The Calvin cycle is directly dependent upon a supply of

A)water and carbon dioxide.
B)carbon dioxide and NADPH.
C)carbon dioxide,NADPH,and ATP.
D)oxygen and carbon dioxide.
E)glucose and carbon dioxidE.

Question 37

In photosynthesis,which of the following molecules will be directly converted into glucose and other organic molecules?

A)RuBP
B)ATP
C)NADPH
D)G3P
E)Carbon dioxide

Question 38

Which of the following is a molecule which helps prepare for the Calvin cycle,rather than participating in it?

A)chlorophyll
B)NADPH
C)ATP
D)RuBP
E)G3P

Question 39

Which part of the cell would be of most interest when in studying production of ATP and NADPH?

A)chloroplast stroma
B)outer chloroplast membrane
C)thylakoids
D)inner chloroplast membrane
E)photosynthetic pigments

Question 40

Which of the following occurs outside the Calvin Cycle?

A)NADPH into NADP⁺
B)Carbon dioxide reduction
C)Electron transport
D)RuBP regeneration
E)Carbon dioxide fixation

Question 41

The Calvin cycle in CAM plants exemplifies the term "light-independent reactions" because

A)CAM plants thrive in dimly-light conditions.
B)the stomata of CAM plants only open and allow carbon dioxide to enter at night.
C)sunlight is not used in chlorophyll synthesis.
D)CAM plants wither and die if exposed to sunlight.
E)the RuBP carboxylase in CAM plants is inhibited by light.

Question 42

Figure:
In the figure,what part of the leaf is indicated by b?

A)mesophyll
B)stoma
C)leaf vein
D)upper epidermis
E)cuticle

Question 43

What is the effect of burning trees on atmospheric levels of carbon dioxide?

A)Carbon dioxide levels increase because trees would ordinarily absorb carbon dioxide.
B)Carbon dioxide levels decrease because trees ordinarily produce carbon dioxide.
C)Carbon dioxide levels are unaffected because plants are not involved in carbon dioxide fixation.
D)Carbon dioxide levels increase because the rate of photosynthesis increases.
E)Carbon dioxide levels are unaffected because forests do not make a significant contribution to global carbon dioxide fixation.

Question 44

What would occur if the thylakoid membrane was highly permeable to hydrogen ions?

A)Chemiosmosis would occur more rapidly.
B)ATP synthesis would be greatly enhanced.
C)ATP synthase complexes would not work.
D)Water would not be split in the light reactions.
E)The electron transport chain would function more efficiently.

Question 45

Why is a molecule that binds to and blocks the action of ATP synthase lethal to plants?

A)ATP synthase splits water and releases oxygen;without the production of oxygen,the plants will die.
B)ATP synthase is the enzyme responsible for carbon dioxide fixation.
C)The ATP produced by ATP synthase powers the Calvin cycle,the ultimate source of all organic molecules made by the plant.
D)When ATP synthase is blocked,the electron transport chain moves electrons backwards to the reaction center.
E)If ATP synthase is blocked,chemiosmosis cannot occur,and as a result the plant will run out of water and dehydratE.

Question 46

Figure:
This figure shows a cross section of a typical plant leaf.What does "c" represent?

A)mesophyll
B)stoma
C)stoma
D)upper epidermis
E)cuticle

Question 47

Figure:
This figure shows a cross section of a typical plant leaf.What does "d" represent?

A)mesophyll
B)stoma
C)vein
D)upper epidermis
E)cuticle

Question 48

Which of the following have the shortest wavelength?

A)radio waves
B)X rays
C)microwaves
D)gamma rays
E)ultraviolet rays

Question 49

Photosystem II evolved before Photosystem I.

Question 50

What would occur if a photosystem contained no antenna molecules?

A)Carbohydrate synthesis would increase.
B)The chloroplast would synthesize more ATP.
C)The Calvin cycle would fix carbon dioxide more rapidly.
D)More oxygen would be released from the splitting of water.
E)No reaction center electrons could become excited.

Question 51

If chlorophyll were altered to absorb green light,what color would be lost from leaves,compared to how they now appear?

A)green
B)blue
C)orange
D)yellow
E)red