Question 1

What group of organisms is thought to responsible for converting about 500 trillion kg of CO2 to carbohydrate each year?

Accepted Answer

A) plant life 
B) phytoplankton 
C) fungi 
D) bacteria 
E) moss 
A) plant life 
B) phytoplankton 
C) fungi 
D) bacteria 
E) moss A

Question 2

Why is it necessary to shut down the Calvin Cycle in the dark when ATP and NADPH levels fall?

Accepted Answer

In the dark,plants cannot make ATP and NADPH via the light reactions.Therefore,these products would have to be supplied by aerobic respiration,which would use up carbohydrates.Since making carbohydrates is the purpose of Calvin Cycle,this would be counterproductive and a waste of energy and time.

Question 3

Which type of photophosphorylation predominates under conditions of high NADP+ concentration and under conditions of high NADPH and low ATP concentration?

Accepted Answer

Under conditions of high NADP⁺ concentration,noncyclic photophosphorylation will probably be favored,since additional NADPH would be needed and this can only be supplied by noncyclic photophosphorylation.Under high NADPH and low ATP concentrations,cyclic photophosphorylation would predominate because it can produce ATP without increasing NADPH concentrations and without NADP⁺.

Question 4

What part of the chlorophyll molecule absorbs light?

Accepted Answer

A) the phytol chain 
B) the porphyrin ring 
C) the iron containing heme group 
D) the polypeptide backbone 
E) the perforin ring 
A) the phytol chain 
B) the porphyrin ring 
C) the iron containing heme group 
D) the polypeptide backbone 
E) the perforin ring

Question 5

The LHCII complex binds pigments and holds them in close contact with one another.What is the advantage of the close contact between the pigments?

Accepted Answer

A) The close contact facilitates rapid energy transfer toward the photosystem interior. 
B) The close contact facilitates rapid energy transfer toward the photosystem exterior. 
C) The close contact helps with fluorescence. 
D) The close contact helps prevent denaturation. 
E) The close contact facilitates renaturation. 
A) The close contact facilitates rapid energy transfer toward the photosystem interior. 
B) The close contact facilitates rapid energy transfer toward the photosystem exterior. 
C) The close contact helps with fluorescence. 
D) The close contact helps prevent denaturation. 
E) The close contact facilitates renaturation.

Question 6

Why does Rubisco show relatively little preference for CO2 as a substrate over O2?

Accepted Answer

A) Both CO2 and O2 bind directly to Rubisco's active site. 
B) CO2 and O2 bind to RuBP,which occupies the active site;their ability to attack RuBP is roughly equal. 
C) Rubisco binds to a regulatory site. 
D) CO2 and O2 bind to a regulatory site instead of the active site. 
E) Both O2 and CO2 are repelled RuBP. 
A) Both CO2 and O2 bind directly to Rubisco's active site. 
B) CO2 and O2 bind to RuBP,which occupies the active site;their ability to attack RuBP is roughly equal. 
C) Rubisco binds to a regulatory site. 
D) CO2 and O2 bind to a regulatory site instead of the active site. 
E) Both O2 and CO2 are repelled RuBP.

Question 7

The excited PSII reaction-center pigment (P680*)transfers a single photoexcited electron to a closely associated,chlorophyll-like molecule called _________.

Accepted Answer

A) theophyllin 
B) carotene 
C) pheophytin 
D) xanthophylls 
E) succinate dehydrogenase 
A) theophyllin 
B) carotene 
C) pheophytin 
D) xanthophylls 
E) succinate dehydrogenase

Question 8

Organisms that use the radiant energy of the sun to convert carbon dioxide to organic molecules like carbohydrates and proteins are called _____.

Accepted Answer

A) chemoautotrophs 
B) chemoheterotrophs 
C) photoautotrophs 
D) photoheterotrophs 
E) didliotrophs 
A) chemoautotrophs 
B) chemoheterotrophs 
C) photoautotrophs 
D) photoheterotrophs 
E) didliotrophs

Question 9

Which type of chlorophyll is found in brown algae,diatoms and certain protozoa?

Accepted Answer

A) Chlorophyll a 
B) Chlorophyll b 
C) Chlorophyll c 
D) Bacteriochlorophyll 
E) carotenoids 
A) Chlorophyll a 
B) Chlorophyll b 
C) Chlorophyll c 
D) Bacteriochlorophyll 
E) carotenoids

Question 10

If water is labeled with 18O,where does the radiolabeled oxygen appear?

Accepted Answer

It appears in molecu

Question 11

A mechanism that is known to regulate basic cell processes,like protein folding,transcription,translation and chloroplast metabolism,by controlling the activity of proteins is known as ________.

Accepted Answer

A) transubstantiation 
B) internal combustion 
C) redox control 
D) oxidation inhibition 
E) reduction counter-regulation 
A) transubstantiation 
B) internal combustion 
C) redox control 
D) oxidation inhibition 
E) reduction counter-regulation

Question 12

Why does an electrochemical potential build up in mitochondria,but not in chloroplasts?

Accepted Answer

A) Proton movement into the thylakoid lumen is compensated for (neutralized)by the movement of other ions. 
B) Proton movement into the intercristal space is compensated for (neutralized)by the movement of other ions. 
C) Proton movement into the cristae lumen is compensated for (neutralized)by the movement of other ions. 
D) The protons in chloroplasts are immediately joined to electrons. 
E) The protons in mitochondria are immediately joined to electrons. 
A) Proton movement into the thylakoid lumen is compensated for (neutralized)by the movement of other ions. 
B) Proton movement into the intercristal space is compensated for (neutralized)by the movement of other ions. 
C) Proton movement into the cristae lumen is compensated for (neutralized)by the movement of other ions. 
D) The protons in chloroplasts are immediately joined to electrons. 
E) The protons in mitochondria are immediately joined to electrons.

Question 13

Across which structure is malate transported for the purpose of storing it in the cell's central vacuole?

Accepted Answer

A) the plasma membrane 
B) the nuclear membrane 
C) the tonoplast membrane 
D) the lysosomal membrane 
E) the ER membrane 
A) the plasma membrane 
B) the nuclear membrane 
C) the tonoplast membrane 
D) the lysosomal membrane 
E) the ER membrane

Question 14

A cluster of what kind of ions is responsible for passing electrons one-at-a-time to the nearby P680+ in the reaction center?

Accepted Answer

A) a cluster of iron ions 
B) a cluster of 4 manganese ions and one calcium ion 
C) a cluster of magnesium ions 
D) a cluster of copper ions 
E) a cluster of manganese ions 
A) a cluster of iron ions 
B) a cluster of 4 manganese ions and one calcium ion 
C) a cluster of magnesium ions 
D) a cluster of copper ions 
E) a cluster of manganese ions

Question 15

Organisms that use the energy stored in inorganic molecules,like ammonia,hydrogen sulfide or nitrites,to convert carbon dioxide to organic molecules like carbohydrates and proteins are called _____.

Accepted Answer

A) chemoautotrophs 
B) chemoheterotrophs 
C) photoautotrophs 
D) photoheterotrophs 
E) didliotrophs 
A) chemoautotrophs 
B) chemoheterotrophs 
C) photoautotrophs 
D) photoheterotrophs 
E) didliotrophs

Question 16

Through what structure in mesophyll cells are C4 products transported to the thick-walled bundle sheath cells?

Accepted Answer

A) lysosomes 
B) plasmodesmata 
C) plasma membrane 
D) cilia 
E) mitochondria 
A) lysosomes 
B) plasmodesmata 
C) plasma membrane 
D) cilia 
E) mitochondria

Question 17

What enzyme is the first enzyme in the C4 Hatch-Slack pathway that carries CO2 into the bundle sheath cells?

Accepted Answer

A) Rubisco 
B) phosphenolpyruvate carboxylase 
C) pyruvate carboxylase 
D) phosphoenolpyruvate decarboxylase 
E) ATP synthase 
A) Rubisco 
B) phosphenolpyruvate carboxylase 
C) pyruvate carboxylase 
D) phosphoenolpyruvate decarboxylase 
E) ATP synthase

Question 18

An investigator radioactively labels CO2 with 14C.He exposes a plant from a temperate climate to the radiolabeled CO2.In what molecule does the 14C first appear to accumulate stably? Where does the 14C appear in a plant that is well adapted for life in a hot,dry habitat?

Accepted Answer

In a temperate climate,the mol

Question 19

The shared properties of the two photosystems (I and II)with respect to protein composition and overall architecture suggest that __________.

Accepted Answer

A) both absorb exactly the same wavelength of light 
B) all photosynthetic reaction centers have evolved from a common ancestral structure that has been conserved for a long time (more than 3 billion years) 
C) all photosynthetic reaction centers have their own unique ancestor 
D) all photosynthetic reaction centers have evolved separately within the last 100,000 years 
E) all photosynthetic reaction centers evolved from unrelated structures 
A) both absorb exactly the same wavelength of light 
B) all photosynthetic reaction centers have evolved from a common ancestral structure that has been conserved for a long time (more than 3 billion years) 
C) all photosynthetic reaction centers have their own unique ancestor 
D) all photosynthetic reaction centers have evolved separately within the last 100,000 years 
E) all photosynthetic reaction centers evolved from unrelated structures

Question 20

The production of ATP in chloroplasts and mitochondria differs in which of the following ways?

Accepted Answer

A) The protons move into the stroma in chloroplasts and out of the mitochondria. 
B) In mitochondria,the force is expressed primarily as an electrochemical potential;in chloroplasts,it is largely,if not exclusively,due to a pH gradient. 
C) In mitochondria,the force is expressed primarily as a pH gradient;in chloroplasts,it is largely,if not exclusively,due to an electrochemical potential. 
D) The protons move into the intermembrane space in chloroplasts and into the thylakoid lumen in mitochondria. 
E) The protons move into the matrix in mitochondria and into the cytoplasm in chloroplasts. 
A) The protons move into the stroma in chloroplasts and out of the mitochondria. 
B) In mitochondria,the force is expressed primarily as an electrochemical potential;in chloroplasts,it is largely,if not exclusively,due to a pH gradient. 
C) In mitochondria,the force is expressed primarily as a pH gradient;in chloroplasts,it is largely,if not exclusively,due to an electrochemical potential. 
D) The protons move into the intermembrane space in chloroplasts and into the thylakoid lumen in mitochondria. 
E) The protons move into the matrix in mitochondria and into the cytoplasm in chloroplasts.

What group of organisms is thought to responsible for converting about 500 trillion kg of CO₂ to carbohydrate each year?

Why is it necessary to shut down the Calvin Cycle in the dark when ATP and NADPH levels fall?

Which type of photophosphorylation predominates under conditions of high NADP⁺ concentration and under conditions of high NADPH and low ATP concentration?

What part of the chlorophyll molecule absorbs light?

The LHCII complex binds pigments and holds them in close contact with one another.What is the advantage of the close contact between the pigments?

Why does Rubisco show relatively little preference for CO₂ as a substrate over O₂?

The excited PSII reaction-center pigment (P680*)transfers a single photoexcited electron to a closely associated,chlorophyll-like molecule called _________.

Organisms that use the radiant energy of the sun to convert carbon dioxide to organic molecules like carbohydrates and proteins are called _____.

Which type of chlorophyll is found in brown algae,diatoms and certain protozoa?

If water is labeled with ¹⁸O,where does the radiolabeled oxygen appear?

A mechanism that is known to regulate basic cell processes,like protein folding,transcription,translation and chloroplast metabolism,by controlling the activity of proteins is known as ________.

Why does an electrochemical potential build up in mitochondria,but not in chloroplasts?

Across which structure is malate transported for the purpose of storing it in the cell's central vacuole?

A cluster of what kind of ions is responsible for passing electrons one-at-a-time to the nearby P680+ in the reaction center?

Organisms that use the energy stored in inorganic molecules,like ammonia,hydrogen sulfide or nitrites,to convert carbon dioxide to organic molecules like carbohydrates and proteins are called _____.

Through what structure in mesophyll cells are C₄ products transported to the thick-walled bundle sheath cells?

What enzyme is the first enzyme in the C₄ Hatch-Slack pathway that carries CO₂ into the bundle sheath cells?

An investigator radioactively labels CO₂ with ¹⁴C.He exposes a plant from a temperate climate to the radiolabeled CO₂.In what molecule does the ¹⁴C first appear to accumulate stably? Where does the ¹⁴C appear in a plant that is well adapted for life in a hot,dry habitat?

The shared properties of the two photosystems (I and II)with respect to protein composition and overall architecture suggest that __________.

The production of ATP in chloroplasts and mitochondria differs in which of the following ways?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics, Enzymes, and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, Function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters

Exam 6: Photosynthesis and the Chloroplast

What group of organisms is thought to responsible for converting about 500 trillion kg of CO2 to carbohydrate each year?

Why is it necessary to shut down the Calvin Cycle in the dark when ATP and NADPH levels fall?

Which type of photophosphorylation predominates under conditions of high NADP+ concentration and under conditions of high NADPH and low ATP concentration?

What part of the chlorophyll molecule absorbs light?

The LHCII complex binds pigments and holds them in close contact with one another.What is the advantage of the close contact between the pigments?

Why does Rubisco show relatively little preference for CO2 as a substrate over O2?

The excited PSII reaction-center pigment (P680*)transfers a single photoexcited electron to a closely associated,chlorophyll-like molecule called _________.

Organisms that use the radiant energy of the sun to convert carbon dioxide to organic molecules like carbohydrates and proteins are called _____.

Which type of chlorophyll is found in brown algae,diatoms and certain protozoa?

If water is labeled with 18O,where does the radiolabeled oxygen appear?

A mechanism that is known to regulate basic cell processes,like protein folding,transcription,translation and chloroplast metabolism,by controlling the activity of proteins is known as ________.

Why does an electrochemical potential build up in mitochondria,but not in chloroplasts?

Across which structure is malate transported for the purpose of storing it in the cell's central vacuole?

A cluster of what kind of ions is responsible for passing electrons one-at-a-time to the nearby P680+ in the reaction center?

Organisms that use the energy stored in inorganic molecules,like ammonia,hydrogen sulfide or nitrites,to convert carbon dioxide to organic molecules like carbohydrates and proteins are called _____.

Through what structure in mesophyll cells are C4 products transported to the thick-walled bundle sheath cells?

What enzyme is the first enzyme in the C4 Hatch-Slack pathway that carries CO2 into the bundle sheath cells?

An investigator radioactively labels CO2 with 14C.He exposes a plant from a temperate climate to the radiolabeled CO2.In what molecule does the 14C first appear to accumulate stably? Where does the 14C appear in a plant that is well adapted for life in a hot,dry habitat?

The shared properties of the two photosystems (I and II)with respect to protein composition and overall architecture suggest that __________.

The production of ATP in chloroplasts and mitochondria differs in which of the following ways?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics, Enzymes, and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, Function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Dna Replication and Repair

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters

What group of organisms is thought to responsible for converting about 500 trillion kg of CO₂ to carbohydrate each year?

Which type of photophosphorylation predominates under conditions of high NADP⁺ concentration and under conditions of high NADPH and low ATP concentration?

Why does Rubisco show relatively little preference for CO₂ as a substrate over O₂?

If water is labeled with ¹⁸O,where does the radiolabeled oxygen appear?

Through what structure in mesophyll cells are C₄ products transported to the thick-walled bundle sheath cells?

What enzyme is the first enzyme in the C₄ Hatch-Slack pathway that carries CO₂ into the bundle sheath cells?

An investigator radioactively labels CO₂ with ¹⁴C.He exposes a plant from a temperate climate to the radiolabeled CO₂.In what molecule does the ¹⁴C first appear to accumulate stably? Where does the ¹⁴C appear in a plant that is well adapted for life in a hot,dry habitat?