photosynthesis Flashcards

Which type of organism obtains energy by metabolizing molecules produced by other organisms?

A) autotrophs

B)heterotrophs

C)decomposers

D)B and C

E) A, B, C

Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?

a. CO2 and glucose

b. h2o and o2

c. adp, pi, and nadp+

e. atp and nadph

What are the products of the light reactions that are subsequently used by the Calvin Cycle?

a.oxygen and carbon dioxide

b.carbon dioxide and RuBP

c. water and carbon

d. electrons and phtons

e. ATP and NADPH

What wavelength of light in the figure is most effective in driving photosynthesis?
A. 625 mm
B. 475 mm
C. 420 mm
D. 730 mm
E. 575 mm

The figure shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different?

A) Green and yellow wavelengths inhibit the absorption of red and blue wavelengths.

B) Oxygen given off during photosynthesis interferes with the absorption of light.

C) Other pigments absorb light in addition to chlorophyll a.

D) Aerobic bacteria take up oxygen, which changes the measurement of the rate of photosynthesis.

In the thylakoid membranes, what is the main role of the antenna pigment molecules?

a. split water and release oxygen to the reaction-center chlorophyll

b. harvest photons and transfer light energy to the reaction-center chlorophyll

c. synthesize ATP from ADP and Pi

d.transfer electrons to ferredoxin and then NADPH

e. concentrate photons within the stroma

The reaction-center chlorophyll of this system is known as P700 because

a. there are 700 chlorophyll molecules at this center

b.this pigment is best at absorbing light with a wavelength of 700nm

c.there are 700 photosytem I components to each chloroplast

d. it absorbs 700 photons per microsecond

e. the plastoquinone reflects light with a wavelength of 700 nm

All of the events listed below occur in the light reactions of photosynthesis except
A) oxygen is produced.
B) NADP+ is reduced to NADPH.
C) carbon dioxide is incorporated into PGA.
D) ADP is phosphorylated to yield ATP.
E) light is absorbed and funneled to reaction-center chlorophyll a.

During photosynthesis, visible light has enough energy to

a. force electrons closer to the nucleus

b. excite electrons

c. split a water molecule into hydrogen and oxygen

d. B and C only

e. A,B, and C

Which of the following statements about the light reactions of photosynthesis are true?

a. The splitting of water molecules provides a source of electrons.

b. Chlorophyll (and other pigments) absorb light energy, which excites electrons.

c. ATP is generated by photophosphorylation.

d. Only A and C are true.

e. A, B, and C are true.

All of the following are directly associated with photosystem II except
A) extraction of hydrogen electrons from the splitting of water.
B) release of oxygen.
C) harvesting of light energy by chlorophyll.
D) NADP+ reductase.
E) P680 reaction-center chlorophyll.

What are the products of noncyclic photophosphorylation?

a. heat and fluorescence

b. ATP and P700

c. ATP and NADPH

d. ADP and NADP

e. P700 and P680

What does cyclic electron flow in the chloroplast produce?

a. ATP

b. NADPH

c. glucose

d. a and b

e. a, b, and c

As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADPH. Where did the extra ATP molecules come from?

A) photosystem II
B) photosystem I
C) cyclic electron flow
D) linear electron flow
E) chlorophyll

In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from

a. the stroma to the photosystem II.

b. the matrix to the stroma.

c. the stroma to the thylakoid space

d. the intermembrane space to the matrix.

e. ATP synthase to NADP+ reductase

Which of the following statements best describes the relationship between photosynthesis and respiration?

a. Respiration is the reversal of the biochemical pathways of photosynthesis.

b. Photosynthesis stores energy in complex organic molecules, while respiration releases it.

c. Photosynthesis occurs only in plants and respiration occurs only in animals.

d. ATP molecules are produced in photosynthesis and used up in respiration.

e. Respiration is anabolic and photosynthesis is catabolic.

Refer to the choices to answer the following questions. Each choice may be used once, more than once, or not at all. Indicate whether the following events occur during

A. photosynthesis

B. respiration

C. both photosynthesis and respiration

D. neither photosynthesis nor respiration

synthesis of ATP by the chemiosmotic mechanism

a. A

b. B

c. C

d. D

Refer to the choices to answer the following questions. Each choice may be used once, more than once, or not at all. Indicate whether the following events occur during

A. photosynthesis

B. respiration

C. both photosynthesis and respiration

D. neither photosynthesis nor respiration

reduction of NADP+

a. A

b. B

c. C

d. D

Refer to the choices to answer the following questions. Each choice may be used once, more than once, or not at all. Indicate whether the following events occur during

A. photosynthesis

B. respiration

C. both photosynthesis and respiration

D. neither photosynthesis nor respiration

the splitting of carbon dioxide to form oxygen gas and carbon compounds

a. A

b. B

c. C

d. D

Where are the molecules of the electron transport chain found in plant cells?

A) thylakoid membranes of chloroplasts
B) stroma of chloroplasts
C) outer membrane of mitochondria
D) matrix of mitochondria
E) cytoplasm

Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?

A) The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, Pi, and NADP+ to the light reactions.
B) The light reactions provide ATP and NADPH to the carbon fixation step of the Calvin cycle, and the cycle provides water and electrons to the light reactions.
C) The light reactions supply the Calvin cycle with CO2 to produce sugars, and the Calvin cycle supplies the light reactions with sugars to produce ATP.
D) The light reactions provide the Calvin cycle with oxygen for electron flow, and the Calvin cycle provides the light reactions with water to split.
E) There is no relationship between the light reactions and the Calvin cycle.

Which of the following is (are) required in the calvin cycle?

A. CO2

B. ATP

C. RuBP

d. A and B only

e. A, B, and C

Which statement is false?

A) Thylakoid membranes contain the photosynthetic pigments.
B) The O2 released during photosynthesis comes from water.
C) RuBP is produced during cyclic electron flow in the light reactions of photosynthesis.
D) The light reactions of photosynthesis provide the energy for the Calvin cycle.
E) When chlorophyll is reduced, it gains electrons.

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.Use the following key:

A.light reactions alone

B.the Calvin cycle alone

C.both the light reactions and the Calvin cycle

D.neither the light reactions nor the Calvin cycle

E.occurs in the chloroplast but is not part of photosynthesis

Produces molecular oxygen (O2)?

a. A

b. B

c. C

d. D

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.Use the following key:

A.light reactions alone

B.the Calvin cycle alone

C.both the light reactions and the Calvin cycle

D.neither the light reactions nor the Calvin cycle

E.occurs in the chloroplast but is not part of photosynthesis

Produces NADPH?

a. A

b. B

c. C

d. D

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.Use the following key:

A.light reactions alone

B.the Calvin cycle alone

C.both the light reactions and the Calvin cycle

D.neither the light reactions nor the Calvin cycle

E.occurs in the chloroplast but is not part of photosynthesis

Produces three-carbon sugars?

a. A

b. B

c. C

d. D

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.Use the following key:

A.light reactions alone

B.the Calvin cycle alone

C.both the light reactions and the Calvin cycle

D.neither the light reactions nor the Calvin cycle

E.occurs in the chloroplast but is not part of photosynthesis

Requires glucose?

a. A

b. B

c. C

d. D

For the following questions, compare the light reactions with the Calvin cycle of photosynthesis in plants.Use the following key:

A.light reactions alone

B.the Calvin cycle alone

C.both the light reactions and the Calvin cycle

D.neither the light reactions nor the Calvin cycle

E.occurs in the chloroplast but is not part of photosynthesis

Inactive in the dark?

a. A

b. B

c. C

d. D

Which of the following is (are) true of the enzyme ribulose bisphosphate carboxylase?
A) It participates in the Calvin cycle.
B) It catalyzes a phosphorylation reaction.
C) It has an affinity for both O2 and CO2.
D) A and C are true.
E) A, B, and C are true.

What are the substrates (normal reactants) for the enzyme RuBP carboxylase?

A) CO2 and O2
B) CO2 and glucose
C) ATP and NADPH
D) triose-P, glucose, and CO2
E) CO2 and ATP

Which of the following statements is true concerning the figure?

a. It represents cell processes involved in C4 photosynthesis.

b. It represents the type of cell structures found in CAM plants.

c. It represents an adaptation that minimizes photorespiration.

d. A and C are true.

e. A, B, and C are true.

Oxygen would inhibit the CO2 fixation reactions in

a. cell I only.

b. cell II only.

c. neither cell I nor cell II.

d. both cell I and cell II.

e. cell I during the night and cell II during the day.

In which cell would you expect photorespiration?

a. Cell I

b. Cell II

c. Cell I at night

d. Cell II at night

e. neither Cell I nor Cell II

Why are C4 plants able to photosynthesize with no apparent photorespiration?
A) They do not participate in the Calvin cycle.
B) They use PEP carboxylase to initially fix CO2.
C) They are adapted to cold, wet climates.
D) They conserve water more efficiently.
E) They exclude oxygen from their tissues.

CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they
A) fix CO2 into organic acids during the night.
B) fix CO2 into sugars in the bundle-sheath cells.
C) fix CO2 into pyruvate in the mesophyll cells.
D) use the enzyme phosphofructokinase, which outcompetes rubisco for CO2.
E) use photosystems I and II at night.A

Photorespiration lowers the efficiency of photosynthesis by preventing the formation of
A) carbon dioxide molecules.
B) 3-phosphoglycerate molecules
C) ATP molecules.
D) ribulose bisphosphate molecules.
E) RuBP carboxylase molecules.

Organisms that can exist with light as an energy source and an inorganic form of carbon and other raw materials

a. are called photoautotrophs.

b. do not exist in nature.

c. are called heterotrophs.

d. are best classified as decomposers.

e. both C and D

If photosynthesizing green algae are provided with CO2 synthesized with heavy oxygen (18O), later analysis will
show that all but one of the following compounds produced by the algae contain the 18O label. That one exception is
A) PGA.
B) PGAL.
C) glucose.
D) RuBP.
E) O2.

A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are not being absorbed by this pigment?
A) red and yellow
B) blue and violet
C) green and yellow
D) blue, green, and red
E) green, blue, and violet

Of the following, what do both mitochondria and chloroplasts have in common?

a. thylakoid membranes

b. chemiosmosis

c. ATP synthase

d. B and C only

e. A, B and C