Question 1

The Calvin cycle includes 15 enzymes, most of which are involved in:

Accepted Answer

A) RuBP carboxylation. 
B) RuBP regeneration. 
C) reduction. 
D) starch synthesis. 
E) ATP synthesis. 
A) RuBP carboxylation. 
B) RuBP regeneration. 
C) reduction. 
D) starch synthesis. 
E) ATP synthesis.

Question 2

Which product(s) of the Calvin cycle is (are) exported from the chloroplast for use by the plant cell?

Accepted Answer

A) triose phosphates 
B) sucrose and glucose 
C) RuBP 
D) NADPH 
A) triose phosphates 
B) sucrose and glucose 
C) RuBP 
D) NADPH

Question 3

In addition to chlorophylls, light-harvesting antennae include other pigments. What is the benefit of these additional pigments?

Accepted Answer

A) increased structural stability of the antenna 
B) narrower range of wavelength reflection 
C) lower antioxidant capacity 
D) enhanced resonance transfer 
E) tighter binding of the antennae to the thylakoid 
A) increased structural stability of the antenna 
B) narrower range of wavelength reflection 
C) lower antioxidant capacity 
D) enhanced resonance transfer 
E) tighter binding of the antennae to the thylakoid

Question 4

Suppose you discovered a mutant strain of spinach in which the thylakoid membranes were slightly permeable to protons, thus allowing a slow leakage. (Remember that normal membranes are not permeable to protons at all.) How might this defect affect the yield of ATP and/or NADPH from the light reactions?

Accepted Answer

A) NADPH yield would decrease. 
B) NADPH yield would increase. 
C) ATP yield would decrease. 
D) ATP yield would increase. 
E) There would be no change. 
A) NADPH yield would decrease. 
B) NADPH yield would increase. 
C) ATP yield would decrease. 
D) ATP yield would increase. 
E) There would be no change.

Question 5

Which of the following compounds is required for the carboxylation step of the Calvin cycle?

Accepted Answer

A) ATP 
B) NADPH 
C) RuBP 
D) 3-PGA 
E) ATP and NADPH 
A) ATP 
B) NADPH 
C) RuBP 
D) 3-PGA 
E) ATP and NADPH

Question 6

In terms of energy production, humans have nothing in common with plants.

Accepted Answer

A) True 
 B)False

Question 7

During photosynthesis, _____ is reduced to _____.

Accepted Answer

A) water; carbon dioxide 
B) carbon dioxide; sugar 
C) oxygen; water 
D) sugar; oxygen 
E) carbon dioxide; oxygen 
A) water; carbon dioxide 
B) carbon dioxide; sugar 
C) oxygen; water 
D) sugar; oxygen 
E) carbon dioxide; oxygen

Question 8

The product of the Calvin cycle is a triose-phosphate sugar that is either exported from the chloroplast or used to regenerate RUBP. How many times must each of the reactions in the Calvin cycle take place in order to complete the synthesis of one 3-carbon triose phosphate sugar molecule?

Accepted Answer

A) 6 
B) 3 
C) 2 
D) 1 
A) 6 
B) 3 
C) 2 
D) 1

Question 9

The first stage in the production of ATP via the oxidation of glucose molecules is referred to as:

Accepted Answer

A) the Calvin cycle. 
B) the citric acid cycle. 
C) glycolysis. 
D) photosynthesis. 
E) the electron transport chain. 
A) the Calvin cycle. 
B) the citric acid cycle. 
C) glycolysis. 
D) photosynthesis. 
E) the electron transport chain.

Question 10

All photosynthetic bacteria possess two functionally distinct photosystems.

Accepted Answer

A) True 
 B)False

Question 11

Over evolutionary time, photosynthesis has, in effect, introduced challenges to itself by producing an oxygen atmosphere because:

Accepted Answer

A) rubisco is an oxygenase. 
B) rubisco is a carboxylase. 
C) O2 is a strong oxidant. 
D) rubisco is an oxygenase and O2 is a strong oxidant. 
E) rubisco is an oxygenase and O2 is a strong reductant. 
A) rubisco is an oxygenase. 
B) rubisco is a carboxylase. 
C) O2 is a strong oxidant. 
D) rubisco is an oxygenase and O2 is a strong oxidant. 
E) rubisco is an oxygenase and O2 is a strong reductant.

Question 12

Photosynthetic eukaryotes have two photosystems. Which of the following hypotheses is believed to explain this?

Accepted Answer

A) Two different ancient photosynthetic bacteria took up residence in a primitive eukaryotic host and are present today as chloroplasts. 
B) An ancient species of photosynthetic bacteria with a single photosystem took up residence in a eukaryotic host and eventually evolved a second photosystem. 
C) An ancient species of photosynthetic bacteria with two photosystems took up residence in a primitive eukaryotic host and exist today as chloroplasts. 
A) Two different ancient photosynthetic bacteria took up residence in a primitive eukaryotic host and are present today as chloroplasts. 
B) An ancient species of photosynthetic bacteria with a single photosystem took up residence in a eukaryotic host and eventually evolved a second photosystem. 
C) An ancient species of photosynthetic bacteria with two photosystems took up residence in a primitive eukaryotic host and exist today as chloroplasts.

Question 13

Predict which of the following would happen if a plant was exposed to a toxin that made the thylakoid membranes permeable to protons.

Accepted Answer

A) The proton gradient across the thylakoid membrane would be eliminated. 
B) The protons necessary to generate NADPH from NADP+ would no longer be present. 
C) The oxidation and reduction of the protein complexes in the electron transport would be prevented. 
D) A reversal of the proton gradient across the thylakoid membrane would result in a higher pH in the thylakoid lumen than in the surrounding stoma. 
A) The proton gradient across the thylakoid membrane would be eliminated. 
B) The protons necessary to generate NADPH from NADP+ would no longer be present. 
C) The oxidation and reduction of the protein complexes in the electron transport would be prevented. 
D) A reversal of the proton gradient across the thylakoid membrane would result in a higher pH in the thylakoid lumen than in the surrounding stoma.

Question 14

As in mitochondria, the inner membrane of a chloroplast is highly convoluted, greatly increasing surface area.

Accepted Answer

A) True 
 B)False

Question 15

Of the compounds listed below, identify which is a product of the Calvin cycle that is exported from the chloroplast for use by the plant cell, and then describe the importance of the other compounds to the metabolism of the plants.
triose phosphate, sucrose and glucose, RuBP, and NADPH

Accepted Answer

Triose phosphates are exported from the

Question 16

Photorespiration occurs because:

Accepted Answer

A) there is more O2 than CO2 in the atmosphere. 
B) rubisco is a slow catalyst. 
C) rubisco is a selective catalyst. 
D) there is more O2 than CO2 and rubisco is a slow catalyst. 
E) there is more O2 than CO2 and rubisco is a selective catalyst. 
A) there is more O2 than CO2 in the atmosphere. 
B) rubisco is a slow catalyst. 
C) rubisco is a selective catalyst. 
D) there is more O2 than CO2 and rubisco is a slow catalyst. 
E) there is more O2 than CO2 and rubisco is a selective catalyst.

Question 17

The primary reducing agent in the Calvin cycle is:

Accepted Answer

A) NADP+. 
B) water. 
C) NADPH. 
D) oxygen. 
E) NAD+. 
A) NADP+. 
B) water. 
C) NADPH. 
D) oxygen. 
E) NAD+.

Question 18

Which of the following is an advantage of having two slightly different photosystems in the chloroplasts?

Accepted Answer

A) Twice as many electrons can be excited by a given amount of light energy. 
B) Cells are able to use light energy at twice the maximum efficiency predicted for cells with a single photosystem. 
C) Cells are able to use both blue and green wavelengths of light for photosynthesis. 
D) Electrons can be extracted from water and used to reduce NADP+ to NADPH. 
A) Twice as many electrons can be excited by a given amount of light energy. 
B) Cells are able to use light energy at twice the maximum efficiency predicted for cells with a single photosystem. 
C) Cells are able to use both blue and green wavelengths of light for photosynthesis. 
D) Electrons can be extracted from water and used to reduce NADP+ to NADPH.

Question 19

Where is the photosynthetic electron transport chain located in plant cells?

Accepted Answer

A) in the inner membrane of the chloroplast 
B) in the outer membrane of the chloroplast 
C) in the stroma of the chloroplast 
D) in the thylakoid membranes of the chloroplast 
A) in the inner membrane of the chloroplast 
B) in the outer membrane of the chloroplast 
C) in the stroma of the chloroplast 
D) in the thylakoid membranes of the chloroplast

Question 20

The occurrence of photorespiration _____ CO2 and _____ ATP.

Accepted Answer

A) reduces; produces 
B) oxidizes; produces 
C) produces; produces 
D) produces; consumes 
E) consumes; consumes 
A) reduces; produces 
B) oxidizes; produces 
C) produces; produces 
D) produces; consumes 
E) consumes; consumes

Exam 8: Photosynthesis: Using Sunlight to Build Carbohydrates

The Calvin cycle includes 15 enzymes, most of which are involved in:

Which product(s) of the Calvin cycle is (are) exported from the chloroplast for use by the plant cell?

In addition to chlorophylls, light-harvesting antennae include other pigments. What is the benefit of these additional pigments?

Which of the following compounds is required for the carboxylation step of the Calvin cycle?

In terms of energy production, humans have nothing in common with plants.

During photosynthesis, _____ is reduced to _____.

The product of the Calvin cycle is a triose-phosphate sugar that is either exported from the chloroplast or used to regenerate RUBP. How many times must each of the reactions in the Calvin cycle take place in order to complete the synthesis of one 3-carbon triose phosphate sugar molecule?

The first stage in the production of ATP via the oxidation of glucose molecules is referred to as:

All photosynthetic bacteria possess two functionally distinct photosystems.

Over evolutionary time, photosynthesis has, in effect, introduced challenges to itself by producing an oxygen atmosphere because:

Photosynthetic eukaryotes have two photosystems. Which of the following hypotheses is believed to explain this?

Predict which of the following would happen if a plant was exposed to a toxin that made the thylakoid membranes permeable to protons.

As in mitochondria, the inner membrane of a chloroplast is highly convoluted, greatly increasing surface area.

Of the compounds listed below, identify which is a product of the Calvin cycle that is exported from the chloroplast for use by the plant cell, and then describe the importance of the other compounds to the metabolism of the plants. triose phosphate, sucrose and glucose, RuBP, and NADPH

Photorespiration occurs because:

The primary reducing agent in the Calvin cycle is:

Which of the following is an advantage of having two slightly different photosystems in the chloroplasts?

Where is the photosynthetic electron transport chain located in plant cells?

The occurrence of photorespiration _____ CO2 and _____ ATP.

Life: Chemical, Cellular, and Evolutionary Foundations

The Molecules of Life

Nucleic Acids and Transcription

Translation and Protein Structure

Organizing Principles: Lipids, Membranes, and Cell Compartments

Making Life Work: Capturing and Using Energy

Cellular Respiration: Harvesting Energy From Carbohydrates and Other Fuel Molecules

Cell Signaling

Cell and Tissue Architecture: Cytoskeleton, Cell Junctions, and Extracellular Matrix

Cell Division: Variations, Regulation, and Cancer

Dna Replication and Manipulation

Genomes

Mutation and Dna Repair

Genetic Variation

Mendelian Inheritance

Inheritance of Sex Chromosomes, Linked Genes, and Organelles

The Genetic and Environmental Basis of Complex Traits

Genetic and Epigenetic Regulation

Genes and Development

Evolution: How Genotypes and Phenotypes Change Over Time

Species and Speciation

Evolutionary Patterns: Phylogeny and Fossils

Human Origins and Evolution

Cycling Carbon

Bacteria and Archaea

Eukaryotic Cells: Origins and Diversity

Being Multicellular

Plant Structure and Function: Moving Photosynthesis Onto Land

Plant Reproduction: Finding Mates and Dispersing Young

Plant Growth and Development

Plant Defense: Keeping the World Green

Plant Diversity

Fungi: Structure, Function, and Diversity

Animal Nervous Systems

Animal Sensory Systems and Brain Function

Animal Movement: Muscles and Skeletons

Animal Endocrine Systems

Animal Cardiovascular and Respiratory Systems

Animal Metabolism, Nutrition, and Digestion

Animal Renal Systems: Water and Waste

Animal Reproduction and Development

Animal Immune Systems

Animal Diversity

Animal Behavior

Population Ecology

Species Interactions, Communities, and Ecosystems

Biomes and Global Ecology

The Anthropocene: Humans As a Planetary Force

Filters

During photosynthesis, _ is reduced to _.

The occurrence of photorespiration _ CO₂ and _ ATP.