Question 1

Which statement describes the functioning of photosystem II?

Accepted Answer

A) Light energy excites electrons in the thylakoid membrane electron transport chain. 
B) Photons are passed along to a reaction-centre chlorophyll. 
C) The P680 chlorophyll donates a pair of protons to NADP⁺, which is thus converted to NADPH. 
D) The electron vacancies in P680⁺ are filled by electrons derived from water. 
E) The splitting of water yields molecular carbon dioxide as a by-product. 
A) Light energy excites electrons in the thylakoid membrane electron transport chain. 
B) Photons are passed along to a reaction-centre chlorophyll. 
C) The P680 chlorophyll donates a pair of protons to NADP⁺, which is thus converted to NADPH. 
D) The electron vacancies in P680⁺ are filled by electrons derived from water. 
E) The splitting of water yields molecular carbon dioxide as a by-product. D

Question 2

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

Accepted Answer

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

Question 3

In autotrophic bacteria, where are the enzymes located that can carry on carbon fixation (reduction of carbon dioxide to carbohydrate)?

Accepted Answer

A) in chloroplast membranes 
B) in chloroplast stroma 
C) in the cytosol 
D) in the nucleoid 
E) in the infolded plasma membrane 
A) in chloroplast membranes 
B) in chloroplast stroma 
C) in the cytosol 
D) in the nucleoid 
E) in the infolded plasma membrane C

Question 4

What does the chemiosmotic process in chloroplasts involve?

Accepted Answer

A) establishment of a proton gradient across the thylakoid membrane 
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 
A) establishment of a proton gradient across the thylakoid membrane 
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

Question 5

To identify the molecule that accepts CO₂, Calvin and Benson manipulated the carbon-fixation cycle by either cutting off CO₂ or cutting off light from cultures of photosynthetic algae. They then measured the concentrations of various metabolites immediately following the manipulation. How would these experiments help identify the CO₂ acceptor? Study the figure above to help you in determining the correct answer.

Accepted Answer

A) The CO₂ acceptor concentration would decrease when either the CO₂ or light are cut off. 
B) The CO₂ acceptor concentration would increase when either the CO₂ or light are cut off. 
C) The CO₂ acceptor concentration would increase when the CO₂ is cut off, but decrease when the light is cut off. 
D) The CO₂ acceptor concentration would decrease when the CO₂ is cut off, but increase when the light is cut off. 
E) The CO₂ acceptor concentration would stay the same regardless of the CO₂ or light. 
A) The CO₂ acceptor concentration would decrease when either the CO₂ or light are cut off. 
B) The CO₂ acceptor concentration would increase when either the CO₂ or light are cut off. 
C) The CO₂ acceptor concentration would increase when the CO₂ is cut off, but decrease when the light is cut off. 
D) The CO₂ acceptor concentration would decrease when the CO₂ is cut off, but increase when the light is cut off. 
E) The CO₂ acceptor concentration would stay the same regardless of the CO₂ or light.

Question 6

Compared to C₃ plants, C₄ plants

Accepted Answer

A) can continue to fix CO₂ even at relatively low CO₂ concentrations and high oxygen concentrations. 
B) have higher rates of photorespiration. 
C) do not use rubisco for carbon fixation. 
D) grow better under cool, moist conditions. 
E) make a four-carbon compound, oxaloacetate, which is then delivered to the citric acid cycle in mitochondria. 
A) can continue to fix CO₂ even at relatively low CO₂ concentrations and high oxygen concentrations. 
B) have higher rates of photorespiration. 
C) do not use rubisco for carbon fixation. 
D) grow better under cool, moist conditions. 
E) make a four-carbon compound, oxaloacetate, which is then delivered to the citric acid cycle in mitochondria.

Question 7

CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they

Accepted Answer

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 photosystem I and photosystem II at night. 
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 photosystem I and photosystem II at night.

Question 8

Use the following information to answer the questions below.
Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted in which areas the bacteria congregated. He noted that the largest groups were found in the areas illuminated by the red and blue light.
-An outcome of this experiment was to help determine

Accepted Answer

A) the relationship between heterotrophic and autotrophic organisms. 
B) the relationship between wavelengths of light and the rate of aerobic respiration. 
C) the relationship between wavelengths of light and the amount of heat released. 
D) the relationship between wavelengths of light and the rate of photosynthesis. 
E) the relationship between the concentration of carbon dioxide and the rate of photosynthesis. 
A) the relationship between heterotrophic and autotrophic organisms. 
B) the relationship between wavelengths of light and the rate of aerobic respiration. 
C) the relationship between wavelengths of light and the amount of heat released. 
D) the relationship between wavelengths of light and the rate of photosynthesis. 
E) the relationship between the concentration of carbon dioxide and the rate of photosynthesis.

Question 9

The NADPH required for the Calvin cycle comes from

Accepted Answer

A) reactions initiated in photosystem I. 
B) reactions initiated in photosystem II. 
C) the citric acid cycle. 
D) glycolysis. 
E) oxidative phosphorylation. 
A) reactions initiated in photosystem I. 
B) reactions initiated in photosystem II. 
C) the citric acid cycle. 
D) glycolysis. 
E) oxidative phosphorylation.

Question 10

In thylakoids, protons travel through ATP synthase from the thylakoid space to the stroma. Therefore, the catalytic "knobs" of ATP synthase would be located

Accepted Answer

A) on the side facing the thylakoid space. 
B) on the ATP molecules themselves. 
C) on the pigment molecules of photosystem I and photosystem II. 
D) on the stromal side of the membrane. 
E) built into the centre of the thylakoid stack (granum). 
A) on the side facing the thylakoid space. 
B) on the ATP molecules themselves. 
C) on the pigment molecules of photosystem I and photosystem II. 
D) on the stromal side of the membrane. 
E) built into the centre of the thylakoid stack (granum).

Question 11

Use the following figure to answer the questions below.
  
-What wavelength of light in the figure is most effective in driving photosynthesis?

Accepted Answer

A) 420 mm 
B) 475 mm 
C) 575 mm 
D) 625 mm 
E) 730 mm 
A) 420 mm 
B) 475 mm 
C) 575 mm 
D) 625 mm 
E) 730 mm

Question 12

The alternative pathways of photosynthesis using the C₄ or CAM systems are said to be compromises. Why?

Accepted Answer

A) Each one minimizes both water loss and rate of photosynthesis. 
B) C₄ compromises on water loss and CAM compromises on photorespiration. 
C) Both minimize photorespiration but expend more ATP during carbon fixation. 
D) CAM plants allow more water loss, while C₄ plants allow less CO₂ into the plant. 
E) C₄ plants allow less water loss but CAM plants allow more water loss. 
A) Each one minimizes both water loss and rate of photosynthesis. 
B) C₄ compromises on water loss and CAM compromises on photorespiration. 
C) Both minimize photorespiration but expend more ATP during carbon fixation. 
D) CAM plants allow more water loss, while C₄ plants allow less CO₂ into the plant. 
E) C₄ plants allow less water loss but CAM plants allow more water loss.

Question 13

A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are being absorbed by this pigment?

Accepted Answer

A) red and yellow 
B) blue and violet 
C) green and yellow 
D) blue, green, and red 
E) green, blue, and yellow 
A) red and yellow 
B) blue and violet 
C) green and yellow 
D) blue, green, and red 
E) green, blue, and yellow

Question 14

The light reactions of photosynthesis supply the Calvin cycle with

Accepted Answer

A) light energy. 
B) CO₂ and ATP. 
C) H₂O and NADPH. 
D) ATP and NADPH. 
E) sugar and O₂. 
A) light energy. 
B) CO₂ and ATP. 
C) H₂O and NADPH. 
D) ATP and NADPH. 
E) sugar and O₂.

Question 15

The reactions that produce molecular oxygen (O)take place in

Accepted Answer

A) the 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) the chloroplast, but are not part of photosynthesis. 
A) the 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) the chloroplast, but are not part of photosynthesis.

Question 16

In a plant cell, where are the ATP synthase complexes located?

Accepted Answer

A) thylakoid membrane only 
B) plasma membrane only 
C) inner mitochondrial membrane only 
D) thylakoid membrane and inner mitochondrial membrane 
E) thylakoid membrane and plasma membrane 
A) thylakoid membrane only 
B) plasma membrane only 
C) inner mitochondrial membrane only 
D) thylakoid membrane and inner mitochondrial membrane 
E) thylakoid membrane and plasma membrane

Question 17

When pigments in an excited state relax back to ground state, they

Accepted Answer

A) release energy as fluorescence and heat. 
B) lose an electron. 
C) release energy as fluorescence. 
D) release energy as heat. 
E) absorb photons. 
A) release energy as fluorescence and heat. 
B) lose an electron. 
C) release energy as fluorescence. 
D) release energy as heat. 
E) absorb photons.

Question 18

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 is

Accepted Answer

A) 3-phosphoglycerate. 
B) glyceraldehyde 3-phosphate (G3P). 
C) glucose. 
D) ribulose bisphosphate (RuBP). 
E) O₂. 
A) 3-phosphoglycerate. 
B) glyceraldehyde 3-phosphate (G3P). 
C) glucose. 
D) ribulose bisphosphate (RuBP). 
E) O₂.

Question 19

The pH of the inner thylakoid space has been measured, as have the pH of the stroma and of the cytosol of a particular plant cell. Which, if any, relationship would you expect to find?

Accepted Answer

A) The pH within the thylakoid is less than that of the stroma. 
B) The pH of the stroma is lower than that of the other two measurements. 
C) The pH of the stroma is higher than that of the thylakoid space but lower than that of the cytosol. 
D) The pH of the thylakoid space is higher than that anywhere else in the cell. 
E) There is no consistent relationship. 
A) The pH within the thylakoid is less than that of the stroma. 
B) The pH of the stroma is lower than that of the other two measurements. 
C) The pH of the stroma is higher than that of the thylakoid space but lower than that of the cytosol. 
D) The pH of the thylakoid space is higher than that anywhere else in the cell. 
E) There is no consistent relationship.

Question 20

In photosynthetic cells, synthesis of ATP by the chemiosmotic mechanism occurs during

Accepted Answer

A) photosynthesis only. 
B) respiration only. 
C) both photosynthesis and respiration. 
D) neither photosynthesis nor respiration. 
E) photorespiration only. 
A) photosynthesis only. 
B) respiration only. 
C) both photosynthesis and respiration. 
D) neither photosynthesis nor respiration. 
E) photorespiration only.

Exam 10: Photosynthesis

Which statement describes the functioning of photosystem II?

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

In autotrophic bacteria, where are the enzymes located that can carry on carbon fixation (reduction of carbon dioxide to carbohydrate)?

What does the chemiosmotic process in chloroplasts involve?

Compared to C₃ plants, C₄ plants

CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they

The NADPH required for the Calvin cycle comes from

In thylakoids, protons travel through ATP synthase from the thylakoid space to the stroma. Therefore, the catalytic "knobs" of ATP synthase would be located

Use the following figure to answer the questions below. -What wavelength of light in the figure is most effective in driving photosynthesis?

The alternative pathways of photosynthesis using the C₄ or CAM systems are said to be compromises. Why?

A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are being absorbed by this pigment?

The light reactions of photosynthesis supply the Calvin cycle with

The reactions that produce molecular oxygen (O)take place in

In a plant cell, where are the ATP synthase complexes located?

When pigments in an excited state relax back to ground state, they

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 is

The pH of the inner thylakoid space has been measured, as have the pH of the stroma and of the cytosol of a particular plant cell. Which, if any, relationship would you expect to find?

In photosynthetic cells, synthesis of ATP by the chemiosmotic mechanism occurs during

Introduction: Evolution and Themes of Biology

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

Dna Tools and Biotechnology

Genomes and Their Evolution

Descent With Modification: a Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity Ii: the Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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