Photosynthesis

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.

What is the primary function of the Calvin cycle?
A) use ATP to release carbon dioxide
B) use NADPH to release carbon dioxide
C) split water and release oxygen
D) transport RuBP out of the chloroplast
E) synthesize simple sugars from carbon dioxide

How is the proton gradient generated in chloroplasts during photosynthesis?
A. Flow of electrons from carrier to carrier in the thylakoid membrane causes pumping of protons across the thylakoid membrane.
B. Light causes protons to flow through protein channels in the thylakoid membrane.
C. Light splits water molecules in the stroma, causing the release of protons.
D. Protons are pumped across the thylakoid membrane using energy from ATP.

What chemical substances are used during the manufacture of organic molecules in photosynthesis?
I. Hydrogen
II. ATP
III. Carbon dioxide
A. I and III only
B. I and II only
C. II and III only
D. I, II and III

All of the events listed below occur in the light dependent 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.

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

) Which of the following are products of the light dependent reactions of photosynthesis that are utilized in the Calvin cycle?
A) CO2 and glucose
B) H2O and O2
C) ADP, Pi, and NADP+
D) electrons and H+
E) ATP and NADPH

Where do the enzymatic reactions of the Calvin cycle take place?
A) stroma of the chloroplast
B) thylakoid membranes
C) outer membrane of the chloroplast
D) electron transport chain
E) thylakoid space

Why do leaves of plants look green?
A. Most of the green light is absorbed by chlorophyll and most of the red and blue light is reflected.
B. Most of the blue light is absorbed by chlorophyll and most of the red and green light is reflected.
C. Most of the red light is absorbed by chlorophyll and most of the green and blue light is reflected.
D. Most of the red and blue light is absorbed by chlorophyll and most of the green light is reflected.

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.

What is the first identifiable product of carbon dioxide fixation in photosynthesis?
A. Ribulose bisphosphate (RuBP)
B. Glycerate3-phosphate (GP)
C. Triose phosphate (TP)
D. Acetyl CoA

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.

What would be the effect of increasing temperature on the rate of photosynthesis in a green plant?
A. It increases constantly.
B. It increases up to a point and then remains constant.
C. It increases up to a point and then decreases.
D. It remains constant.

How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?
A) 2
B) 4
C) 6
D) 8
E) 10

Pigments are extracted from the leaves of a green plant. White light is then passed through the solution of pigments. What effect do the leaf pigments have on the white light?
A. Green wavelengths are absorbed and red and blue wavelengths are transmitted.
B. Red and blue wavelengths are absorbed and green wavelengths are transmitted.
C Blue wavelengths are absorbed and green and red wavelengths are transmitted.
D. Green and red wavelengths are absorbed and blue wavelengths are transmitted.

Where is chlorophyll found in a plant cell?
A. Thylakoid membranes
B. Stroma
C. Matrix
D. Cristae

Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes?
A) the splitting of water
B) the absorption of light energy by chlorophyll
C) the flow of electrons from photosystem II to photosystem I
D) the synthesis of ATP
E) the reduction of NADP+

Why is the action spectrum for photosynthesis similar to the absorption spectra of photosynthetic pigments?
A. Photosynthetic pigments have the same optimum temperature as the enzymes used in photosynthesis.
B. Plants absorb the same photosynthetic pigments for use in photosynthesis.
C. Only wavelengths of light absorbed by pigments can be used in photosynthesis.
D. The amount of energy absorbed by photosynthetic pigments is equal to the activation energy for photosynthesis.

Which of the following processes is most directly driven by light energy?
A) creation of a pH gradient by pumping protons across the thylakoid membrane
B) carbon fixation in the stroma
C) reduction of NADP+ molecules
D) removal of electrons from chlorophyll molecules
E) ATP synthesis

Where does the Calvin cycle/ Light Independent reaction take place?
A) stroma of the chloroplast
B) thylakoid membrane
C) cytoplasm surrounding the chloroplast
D) chlorophyll molecule
E) outer membrane of the chloroplast

A plant is exposed to increasing light intensity from very dim to bright light, while the carbon dioxide concentration and temperature are kept at an optimum level. What will happen to the rate of oxygen production?
A. It will increase exponentially.
B. It will remain constant.
C. It will decrease to a minimum level.
D. It will increase to a maximum level.

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

In mitochondria, chemiosmosis translocates via active transport protons (H+) from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates via active transport protons (H+) 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.

What is the source of the oxygen released into the air as a product of photosynthesis?

A. Chlorophyll
B. Carbon dioxide only
C. Water only
D. Both water and carbon dioxide

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.

What is needed in photosynthesis to convert carbon dioxide into organic molecules?
A. Light and hydrogen from the splitting of water
B. Light and oxygen from the splitting of water
C. ATP and hydrogen from the splitting of water
D. ATP and oxygen from the splitting of water

What is the primary function of the light dependent reactions of photosynthesis?
A) to produce energy-rich glucose from carbon dioxide and water
B) to produce ATP and NADPH
C) to produce NADPH used in respiration
D) to convert light energy to the chemical energy of PGAL
E) to use ATP to make glucose

In a plant cell, where are the ATP synthase complexes located?
A) thylakoid membrane
B) plasma membrane
C) inner mitochondrial membrane
D) A and C
E) A, B, and C

What is the advantage of having a small volume inside the thylakoids of the chloroplast?
A. A high proton/ hydrogen concentration is rapidly developed.
B. A high electron concentration is rapidly developed.
C. Photosynthetic pigments are highly concentrated.
D. Enzymes of the Calvin cycle are highly concentrated.

What substance is moved into the thylakoids of the chloroplast using energy derived from light?
A. Carbon dioxide (CO2 )
B. Protons (H+)
C. Glycerate 3-phosphate (GP)
D. Adenosine triphosphate (ATP)

What does the chemiosmotic process in chloroplasts involve?
A) establishment of a proton/ hydrogen ion gradient
B) diffusion of electrons through the thylakoid membrane
C) reduction of water to produce ATP energy
D) movement of water by osmosis into the thylakoid space from the stroma
E) formation of glucose, using carbon dioxide, NADPH, and ATP

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 two colours of light does chlorophyll absorb most?
A. Red and yellow
B. Green and blue
C. Red and green
D. Red and blue

Which of the following features is/are present in mitochondria but not in chloroplasts?
I. DNA and ribosomes
II. Outer and inner membranes
III. Cristae