BIO 1081 Exam 3 - photo only

University of Cincinnati BIO 1081 Dr. Mosley

Where is the electron transport chain located in the chloroplast (during the light-dependent reactions)?

a. Stroma

b. Thylakoid membrane

c. Outer membrane

d. Inner membrane

b. Thylakoid membrane

What is the enzyme's name that catalyzes carbon dioxide fixation by attaching it to ribulose-1,5- bisphosphate in the Calvin cycle?

a. RuBisCO

b. PEP carboxylase

c. ATP synthase

d. NADP+ reductase

a. RuBisCO

What is the ultimate source of energy for photosynthesis?

a. Oxygen

b. Carbon dioxide

c. Glucose

d. Sunlight

d. Sunlight

Which of the following is NOT a stage in the Calvin cycle?

a. Carbon fixation

b. Reduction

c. Oxidation

d. Regeneration of ribulose-1,5- bisphosphate

c. Oxidation

Which of the following statements is true regarding C4 plants?

a. They fix carbon dioxide during the day.

b. They utilize PEP carboxylase for carbon fixation.

c. They do not undergo photosynthesis.

d. They produce a 3-carbon molecule as the first stable product.

b. They utilize PEP carboxylase for carbon fixation.

At which wavelength does photosystem I (PSI) primarily absorb light during the photosynthetic process?

a. 680 nm

b. 700 nm

c. 450 nm

d. 650 nm

b. 700 nm

What is the purpose of the proton gradient established during the light-dependent reactions?

a. To split water molecules

b. To create oxygen

c. To generate ATP through chemiosmosis

d. To synthesize glucose

c. To generate ATP through chemiosmosis

What is the first stable product of the Calvin cycle?

a. Fructose-1,6-bisphosphate

b. G3P

c. 3PG

d. RUBP

c. 3PG

In photosynthesis, what is the primary function of photosystem II (PSII)?

a. Absorbing photons of light

b. Splitting water to release oxygen

c. Pumping protons into the thylakoid space

d. Transferring electrons to NADP+ to produce NADPH

b. Splitting water to release oxygen

In the Calvin Cycle, most of the carbons are used to

a. Regenerate RuBisCO

b. Synthesize ATP

c. Regenerate RuBP

d. Regenerate Oxaloacetate

c. Regenerate RuBP

In photosynthesis, where is chlorophyll “a” mainly located?

a. In the stroma of chloroplasts

b. In the thylakoid membrane

c. In the cytoplasm

d. In the mitochondria

b. In the thylakoid membrane

Which of the following statements is true about chlorophyll?

a. chlorophyll A absorbs violet-blue light and chlorophyll B absorbs red-orange light

b. chlorophyll B absorbs violet-blue light and chlorophyll A absorbs red light

c. chlorophyll A and B absorb green light

d. None of the above is true

a. chlorophyll A absorbs violet-blue light and chlorophyll B absorbs red-orange light

In photosynthesis, what is the primary pigment responsible for capturing photons of light in photosystems?

Chlorophyll a

The light-dependent reactions of photosynthesis occur in the

a. Stroma

b. Mitochondrial matrix

c. Thylakoid membrane

d. Cytoplasm

c. Thylakoid membrane

Which of the following is not a product of the light-dependent reactions of photosynthesis?

a. O2

b. ATP

c. NADPH

d. Sugar

d. Sugar

Which of the following is the photosynthetic stage that produces oxygen?

a. The light-dependent reactions

b. Chemiosmosis

c. The Calvin cycle

d. Photorespiration

a. The light-dependent reactions

Which of the following occurs during the light-independent reactions of photosynthesis?

a. Water is converted into hydrogen and water.

b. CO2 is converted into sugars.

c. Chlorophyll acts as an enzyme.

d. Nothing occurs; the plant rests in the dark

b. CO2 is converted into sugars.

Compared to long-wavelength photons, short-wavelength photons have

a. more energy.

b. energy not available to plant cells.

c. an insignificant amount of energy.

d. an equal amount of energy

a. more energy.

When white light strikes a blue pigment, blue light is

a. reduced.

b. absorbed.

c. converted to chemical energy.

d. reflected.

d. reflected.

When a photon is absorbed by a molecule, the photon

a. loses its ability to generate any energy.

b. raises the molecule from a ground state of low energy to an excited state.

c. affects the molecule in ways that are not clearly understood.

d. causes a change in the velocity of the wavelengths.

b. raises the molecule from a ground state of low energy to an excited state.

In noncyclic photophosphorylation, electrons from _______ replenish chlorophyll molecules that have given up electrons.

a. CO2

b. water

c. NADPH + H+

d. O2 gas

b. water

In both photosynthesis and respiration, protons are pumped across a membrane during

a. electron transport.

b. photolysis.

c. CO2 fixation.

d. reduction of O2.

a. electron transport.

Photorespiration

a. results in CO2 fixation.

b. uses ATP and NADPH produced in the light reactions.

c. generates a proton gradient.

d. results in the synthesis of glucose.

b. uses ATP and NADPH produced in the light reactions.

In C4 plants, the function of the four-carbon compound that is synthesized in the mesophyll cells is to

a. reduce NADP+.

b. combine with CO2 to produce glucose.

c. carry CO2 to the bundle sheath cells.

d. drive the synthesis of ATP.

c. carry CO2 to the bundle sheath cells.

In the thylakoid membranes, what is the main role of the pigment molecules in a light-harvesting complex?

a. Transfer light energy to the reaction-center chlorophyll.

b. Concentrate photons within the stomata.

c. Transfer electrons to ferredoxin and then NADPH.

d. Synthesize ATP from ADP and inorganic phosphate group.

a. Transfer light energy to the reaction-center chlorophyll.

Which of the events listed below occurs in the light reactions of photosynthesis?

a. Light is absorbed and funneled to reaction-center chlorophyll a.

b. Carbon dioxide is incorporated into PGA.

c. NADP is produced.

d. NADPH is reduced to NADP+.

a. Light is absorbed and funneled to reaction-center chlorophyll a.

What is the primary function of the Calvin cycle?

a. Transport RuBP out of the chloroplast

b. Use NADPH to release carbon dioxide.

c. Synthesize simple sugars from carbon dioxide.

d. Split water and release oxygen.

c. Synthesize simple sugars from carbon dioxide.

When a photon is absorbed by chlorophyll,

A. the chlorophyll becomes “excited,” or energized.

B. a greater number of light wavelengths can be absorbed.

C. ATP is split into ADP, phosphate, and energy.

D. hydrogen ions are released

A. the chlorophyll becomes “excited,” or energized.

If the gene encoding the enzyme rubisco is mutated such that it is non-functional, the process that would be affected is the ability to
A. make ATP.     B. fix carbon.
C. make O₂.        D. make NADPH.

B. fix carbon.

Most plants incorporate carbon dioxide into sugars by means of a cycle of reactions called the 
A. CAM cycle.              B. carbon cycle.
C. Calvin cycle.            D. Krebs cycle.

C. Calvin cycle.

CO2 binds to ________ in the Calvin cycle

A. ribulose bisphosphate   B. glucose

C. water                           D. NADPH

A. ribulose bisphosphate