Exam 1 Practice Flashcards
What is the atomic number of an atom that has 6 protons, 6 neutrons, and 6 electrons?
12
18
1
0
6
6
Which of these refers to atoms with the same atomic number but different atomic masses?
These atoms have different numbers of protons.
These atoms have different numbers of electrons.
These atoms are different elements.
These atoms are isomers.
These atoms are isotopes.
These atoms are isotopes.
Fluorine’s atomic number is 9 and its atomic mass is 19. How many neutrons does fluorine have?
81
28
10
19
9
10
An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many protons does boron have?
0
5
6
16
11
5
Each element is unique and different from other elements because of the number of protons in the nuclei of its atoms. Which of the following indicates the number of protons in an atom’s nucleus?
atomic mass
atomic number
atomic weight
mass weight
mass number
atomic number
The innermost electron shell of an atom can hold up to _____ electrons.
18
8
1
32
2
2
Which of these relationships is true of an uncharged atom?
The number of neutrons is equal to the number of protons.
The atomic mass is equal to the number of electrons.
The atomic mass is equal to the atomic number.
The number of protons is equal to the number of electrons.
The number of electrons is equal to the number of neutrons.
The number of protons is equal to the number of electrons.
What determines the types of chemical reactions that an atom participates in?
its atomic mass
the number of electrons in the outermost electron shell
its atomic number
the number of protons it contains
the number of electrons in the innermost electron shell
the number of electrons in the outermost electron shell
What is the difference between starch and cellulose?
Starch is made of alpha glucose monomers. All oxygen bonds are down, which makes it curve. Used for energy STORAGE. Cellulose is made of beta glucose monomers. Oxygen bonds alternate, making it straight. Used for STRUCTURE.
A(n) _____ refers to two or more atoms held together by covalent bonds. molecule shell isotope ion community
Molecule
Atoms with the same number of protons but with different electrical charges _____. are different ions have different numbers of neutrons have different atomic masses have different atomic numbers are different isotopes
are different ions
In salt, what is the nature of the bond between sodium and chlorine?
hydrogen
ionic
hydrophobic
nonpolar
covalent
polar covalent
Ionic
What is the result of the animated process? a positively charged sodium ion and a negatively charged chlorine ion a negatively charged sodium ion and a negatively charged chlorine ion a positively charged sodium ion and a positively charged chlorine ion covalent bond formation a negatively charged sodium ion and a positively charged chlorine ion
a positively charged sodium ion and a negatively charged chlorine ion
An ionic bond involves _____. an attraction between ions of opposite charge the unequal sharing of an electron pair the sharing of a single pair of electrons water avoidance no atoms other than sodium and chlorine
an attraction between ions of opposite charge
Please refer to the figure to answer the following question.
Which drawing depicts the electron configuration of neon ( 2010Ne)?
A B C D E
E
What type of bond is joining the two hydrogen atoms?
hydrophilic ionic hydrophobic covalent hydrogen
Covalent
Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature?
the release of heat by the formation of hydrogen bonds
water’s change in density when it condenses
water’s high surface tension
the absorption of heat by the breaking of hydrogen bonds
water’s ability to dissolve molecules in the air
the absorption of heat by the breaking of hydrogen bonds
Water is able to form hydrogen bonds because
oxygen has a valence of 2.
each of the hydrogen atoms in a water molecule is weakly negative in charge.
the water molecule is shaped like a tetrahedron.
the oxygen atom in a water molecule has a weak positive charge.
the bonds that hold together the atoms in a water molecule are polar covalent bonds.
the bonds that hold together the atoms in a water molecule are polar covalent bonds.
Which of the following effects is produced by the high surface tension of water?
Lakes don’t freeze solid in winter, despite low temperatures.
Organisms resist temperature changes, although they give off heat due to chemical reactions.
A water strider can walk across the surface of a small pond.
The pH of water remains exactly neutral.
Water can act as a solvent.
A water strider can walk across the surface of a small pond.
Water’s high specific heat is mainly a consequence of the
absorption and release of heat when hydrogen bonds break and form.
high specific heat of oxygen and hydrogen atoms.
inability of water to dissipate heat into dry air.
fact that water is a poor heat conductor.
small size of the water molecules.
absorption and release of heat when hydrogen bonds break and form
Which type of bond must be broken for water to vaporize?
ionic bonds
hydrogen bonds
polar covalent bonds
nonpolar covalent bonds
covalent bonds
hydrogen bonds
Why does ice float in liquid water?
The liquid water molecules have more kinetic energy and thus support the ice. Ice always has air bubbles that keep it afloat.
The crystalline lattice of ice causes it to be denser than liquid water.
The ionic bonds between the molecules in ice prevent the ice from sinking.
Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water.
Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water.
What is the pH of a solution with a hydrogen ion [H+] concentration of 10-8 M?
pH 8
pH 6
pH 4
pH 2
pH 10
pH 8
If the pH of a solution is decreased from 9 to 8, it means that the
concentration of OH- has increased 10-fold (10X) compared to what it was at pH 9; concentration of H+ remains unchanged.
concentration of H+ has decreased to one-tenth (1/10) what it was at pH 9; concentration of OH-remains unchanged.
concentration of H+ has increased 10-fold (10X) compared to what it was at pH 9; concentration of OH- remains unchanged.
concentration of OH- has decreased to one-tenth (1/10) what it was at pH 9; concentration of H+remains unchanged.
concentration of H+ has increased 10-fold (10X) compared to what it was at pH 9 and concentration of OH– has decreased to one-tenth (1/10) what it was at pH 9.
concentration of H+ has increased 10-fold (10X) compared to what it was at pH 9 and concentration of OH– has decreased to one-tenth (1/10) what it was at pH 9.
The bonds that are broken when water vaporizes are
ionic bonds.
polar covalent bonds.
covalent bonds between atoms within water molecules.
hydrogen bonds between water molecules.
nonpolar covalent bonds
hydrogen bonds between water molecules.
How many electron pairs does carbon share in order to complete its valence shell?
1
4
3
8
2
4
Which of the following is not a polymer?
glucose
starch
cellulose
chitin
DNA
Glucose
What is the chemical mechanism by which cells make polymers from monomers?
hydrolysis
dehydration reactions
the formation of disulfide
bridges between monomers
ionic bonding of monomers
phosphodiester linkages
Dehydration reactions
Glycogen is _____.
a transport protein that carries oxygen a polysaccharide found in animals
a polysaccharide found in plant cell walls
the form in which plants store sugars
a source of saturated fat
a polysaccharide found in animals
glucose + glucose —> _____ by _____.
sucrose + water … dehydration synthesis
starch + water … dehydration synthesis
maltose + water … dehydration synthesis
lactose + water … hydrolysis
cellulose + water … hydrolysis
maltose + water … dehydration synthesis
Which of these is a source of lactose?
sugar
beets
potatoes
milk
starch
sugar cane
Milk
Which of these is a polysaccharide?
glucose
sucrose
lactose
galactose
cellulose
Cellulose
_____ is the most abundant organic compound on Earth.
Glycogen
Lactose
Starch
Cellulose
Glucose
Cellulose
Which of the following is true of both starch and cellulose?
They are both used for energy storage in plants.
They can both be digested by humans.
They are both structural components of the plant cell wall.
They are geometric isomers of each other.
They are both polymers of glucose.
They are both polymers of glucose.
Which of the following is true of cellulose?
It is a storage polysaccharide for energy in animal cells.
It is a polymer composed of sucrose monomers.
It is a major structural component of plant cell walls.
It is a major structural component of animal cell plasma membranes.
It is a storage polysaccharide for energy in plant cells.
It is a major structural component of plant cell walls.
Which of these is NOT a lipid?
cholesterol
phospholipid
wax
RNA
steroids
RNA
This figure is an example of a(n) _____.
protein
unsaturated fat
nucleic acid
steroid
saturated fat
Saturated Fat
Which of these is a phospholipid?
Which of these is rich in unsaturated fats?
olive oil
butter
beef fat
a fat that is solid at room temperature
lard
Olive Oil
A function of cholesterol that does not harm health is its role _____.
the most abundant male sex hormone
as the primary female sex hormone
as a component of animal cell membranes
All of cholesterol’s effects cause the body harm.
in calcium and phosphate metabolism
as a component of animal cell membranes
The molecule shown in the figure is a
polypeptide.
unsaturated fatty acid.
saturated fatty acid.
triacylglycerol.
polysaccharide.
unsaturated fatty acid.
Proteins are polymers of _____.
amino acids
nucleotides
CH2O units
glycerol
hydrocarbons
amino acids
What type of bond joins the monomers in a protein’s primary structure?
S - S
hydrophobic
peptide
hydrogen
ionic
peptide
Which of these illustrates the secondary structure of a protein?
The secondary structure of a protein results from _____.
hydrogen bonds
peptide bonds
hydrophobic interactions
ionic bonds bonds between sulfur atoms
hydrogen bonds
Tertiary structure is NOT directly dependent on _____.
bonds between sulfur atoms
ionic bonds
peptide bonds
hydrogen bonds
hydrophobic interactions
peptide bonds
The bonding of two amino acid molecules to form a larger molecule requires
both the release of a carbon dioxide molecule and the addition of a nitrogen atom.
the addition of a water molecule.
the release of a carbon dioxide molecule.
the addition of a nitrogen atom.
the release of a water molecule.
the release of a water molecule.
There are 20 different amino acids. What makes one amino acid different from another?
different amino groups attached to an alpha (α) carbon
different carboxyl groups attached to an alpha (α) carbon
different side chains (R groups) attached to an alpha (α) carbon
different alpha (α) carbons different asymmetric carbons
different side chains (R groups) attached to an alpha (α) carbon
Which type of interaction stabilizes the alpha (α) helix and the beta (β) pleated sheet structures of proteins?
hydrogen bonds
ionic bonds
hydrophobic interactions
peptide bonds
nonpolar covalent bonds
hydrogen bonds
The structure depicted in the figure shows the
1-4 linkage of the β glucose monomers of cellulose.
β pleated sheet secondary structure of a polypeptide.
1-4 linkage of the α glucose monomers of starch.
α helix secondary structure of a polypeptide.
double helical structure of a DNA molecule.
α helix secondary structure of a polypeptide
Which of the following descriptions best fits the class of molecules known as nucleotides?
a nitrogenous base and a pentose sugar
a nitrogenous base, a phosphate group, and a pentose sugar
a pentose sugar and a purine or pyrimidine a nitrogenous base and a phosphate group a phosphate group and an adenine or uracil
a nitrogenous base, a phosphate group, and a pentose sugar
Which of the following statements best summarizes the structural differences between DNA and RNA?
DNA nucleotides contain a different sugar than RNA nucleotides.
RNA is a protein, whereas DNA is a nucleic acid.
RNA is a protein, whereas DNA is a nucleic acid; and RNA is a double helix, but DNA is single-stranded.
RNA is a double helix, but DNA is single-stranded
. DNA is a protein, whereas RNA is a nucleic acid.
DNA nucleotides contain a different sugar than RNA nucleotides.
he structure of a chloroplast is closely tied to its function as the site of photosynthesis.
Some of the following statements are true for chloroplasts; others are true for mitochondria.
Which statements are true for chloroplasts? Select the three that apply.
They contain the green pigment chlorophyll.
They are the sites of reactions that convert solar energy into chemical energy.
Their matrix contains enzymes that function in cellular respiration. Their inner membrane has infoldings called cristae.
They have membranous sacs called thylakoids that are surrounded by a fluid called stroma.
They are the sites of reactions that convert chemical energy to ATP.
They contain the green pigment chlorophyll.
They are the sites of reactions that convert solar energy into chemical energy
They have membranous sacs called thylakoids that are surrounded by a fluid called stroma.
Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?
smooth endoplasmic reticulum
mitochondrion
lysosome
ribosome
contractile
vacuole
smooth endoplasmic reticulum
Which structure is the site of the synthesis of proteins that may be exported from the cell?
rough ER
plasmodesmata
tight junctions
Golgi vesicles
lysosomes
rough ER
Which of the following is a compartment that often takes up much of the volume of a plant cell?
Golgi apparatus
peroxisome
mitochondrion
lysosome
vacuole
vacuole
Organelles other than the nucleus that contain DNA include
chloroplasts.
mitochondria.
ribosomes.
mitochondria and chloroplasts only
ribosomes,
mitochondria, and chloroplasts
mitochondria and chloroplasts only
Which of the following are capable of converting light energy to chemical energy?
Golgi bodies
mitochondria
chloroplasts
peroxisomes
leucoplasts
chloroplasts
Why isn’t the mitochondrion classified as part of the endomembrane system?
It has too many vesicles.
It is not attached to the outer nuclear envelope.
Its structure is not derived from the ER.
It only has two membrane layers.
It is not involved in protein synthesis.
Its structure is not derived from the ER.
Which of the following is present in a prokaryotic cell?
mitochondrion
ER
nuclear envelope
ribosome
chloroplast
ribosome
Which statement correctly characterizes bound ribosomes?
The most common location for bound ribosomes is the cytoplasmic surface of the plasma membrane.
Bound ribosomes are enclosed in their own membrane.
Bound ribosomes generally synthesize membrane proteins and secretory proteins. Bound and free ribosomes are structurally different.
All of the above.
Bound ribosomes generally synthesize membrane proteins and secretory proteins.
Cells of the pancreas will incorporate radioactively labeled amino acids into proteins. This “tagging” of newly synthesized proteins enables a researcher to track their location. In this case, we are tracking an enzyme secreted by pancreatic cells. What is its most likely pathway?
nucleus→ER→Golgi
ER→Golgi→vesicles that fuse with plasma membrane
ER→lysosomes→vesicles that fuse with plasma membrane
Golgi→ER→lysosome ER→Golgi→nucleus
ER→Golgi→vesicles that fuse with plasma membrane
Which structure is common to plant and animal cells?
centriole
wall made of cellulose
mitochondrion
central vacuole
chloroplast
mitochondrion
Which structure-function pair is mismatched?
Golgi; protein trafficking
nucleolus; production of ribosomal subunits
microtubule; muscle contraction
ribosome; protein synthesis
lysosome; intracellular digestion
microtubule; muscle contraction
The cilia and flagella of eukaryotic cells are composed of _____.
intermediate filaments
tonofilaments
microtubules pili
microfilaments
microtubules
Cells can be described as having a cytoskeleton of internal structures that contribute to the shape, organization, and movement of the cell. Which of the following are part of the cytoskeleton?
lysosomes
nucleoli
mitochondria
the nuclear envelope
microfilaments
microfilaments
Which of the following types of molecules are the major structural components of the cell membrane?
glycoproteins and cholesterol
phospholipids and cellulose
phospholipids and proteins
nucleic acids and proteins
proteins and cellulose
phospholipids and proteins
For the following question, match the labeled component of the cell membrane (see the figure) with its description.
peripheral protein
A B C D E
D
For the following question, match the labeled component of the cell membrane (see the figure) with its description.
cholesterol
A B C D E
E
For the following question, match the labeled component of the cell membrane (see the figure) with its description.
fiber of the extracellular matrix
A B C D E
A
For the following question, match the labeled component of the cell membrane (see the figure) with its description.
microfilament of the cytoskeleton
A B C D E
C
According to the fluid mosaic model of cell membranes, which of the following is a true statement about membrane phospholipids?
They are free to depart from the membrane and dissolve in the surrounding solution. They frequently flip-flop from one side of the membrane to the other.
They occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the membrane.
They have hydrophilic tails in the interior of the membrane.
They can move laterally along the plane of the membrane.
They can move laterally along the plane of the membrane
What kinds of molecules pass through a cell membrane most easily?
ionic
large and hydrophobic
small and hydrophobic
large polar monosaccharides such as glucose
small and hydrophobic
Which of the following is a characteristic feature of a carrier protein in a plasma membrane?
It requires the expenditure of cellular energy to function.
It has few, if any, hydrophobic amino acids.
It works against diffusion.
It is a peripheral membrane protein.
It exhibits a specificity for a particular type of molecule.
It exhibits a specificity for a particular type of molecule.
When a plant cell, such as one from a peony stem, is submerged in a very hypotonic solution, what is likely to occur?
the cell will become flaccid
the cell will become turgid
plasmolysis will shrink the interior
the cell membrane will lyse
the cell will burst
the cell will become turgid
According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly
embedded in a lipid bilayer.
randomly oriented in the membrane, with no fixed inside-outside polarity.
spread in a continuous layer over the inner and outer surfaces of the membrane.
free to depart from the fluid membrane and dissolve in the surrounding solution. confined to the hydrophobic core of the membrane.
embedded in a lipid bilayer.
Based on the figure above, which of these experimental treatments would increase the rate of sucrose transport into the cell?
adding a substance that makes the membrane more permeable to hydrogen ions
decreasing extracellular sucrose
concentration decreasing extracellular
pH decreasing cytoplasmic
pH adding an inhibitor that blocks the regeneration of ATP
decreasing extracellular pH
When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated?
It is transported to specific organs such as the brain.
It is used to store energy as more ATP.
It is lost to the environment.
It is used to power yet more cellular work.
It is used to generate ADP from nucleotide precursors.
It is lost to the environment.
In general, enzymes are what kinds of molecules?
minerals
carbohydrates
nucleic acids
proteins
lipids
proteins
Enzymes work by _____.
reducing EA
An enzyme _____.
is an organic catalyst
is a inorganic catalyst
is a source of energy for endergonic reactions
can bind to nearly any molecule
increases the EA of a reaction
is an organic catalyst
What name is given to the reactants in an enzymatically catalyzed reaction?
active sites
substrate
reactors
EA products
substrate
As a result of its involvement in a reaction, an enzyme _____.
is unchanged
is used up loses energy
permanently alters its shape.
loses a phosphate group
is unchanged
What is the correct label for “A”?
substrate
energy ATP
energy of activation
uphill enzyme energy
energy of activation
The active site of an enzyme is the region that
is inhibited by the presence of a coenzyme or a cofactor.
binds the products of the catalytic reaction.
binds allosteric regulators of the enzyme.
is involved in the catalytic reaction of the enzyme.
is involved in the catalytic reaction of the enzyme.
What process occurs in Box A?
glycolysis
oxidative phosphorylation
electron transport
electron transport and oxidative phosphorylation
the citric acid cycle
glycolysis
What process occurs within Box B?
the citric acid cycle
oxidative phosphorylation
photophosphorylation
electron transport
glycolysis
The citric acid cycle
What molecule is indicated by the letter D?
ATP
oxygen
glucose
water
pyruvate
oxygen
Where does glycolysis takes place?
mitochondrial intermembrane space
cytosol
mitochondrial matrix
mitochondrial inner membrane
mitochondrial outer membrane
cytosol
How many NADH are produced by glycolysis?
1
4
5
3
2
2
In glycolysis, ATP molecules are produced by _____.
cellular respiration
oxidative phosphorylation
photosynthesis
photophosphorylation
substrate-level phosphorylation
substrate-level phosphorylation
Which of these is NOT a product of glycolysis?
pyruvate
ATP
NADH
FADH2
FADH2
In glycolysis, what starts the process of glucose oxidation?
NADPH
hexokinase
ADP
ATP
FADH2
ATP
In glycolysis there is a net gain of _____ ATP.
2
4
1
5
3
2
During glycolysis, when glucose is catabolized to pyruvate, most of the energy of glucose is
used to phosphorylate fructose to form fructose-6-phosphate.
retained in the pyruvate.
stored in the NADH produced.
transferred directly to ATP.
transferred to ADP, forming ATP.
retained in the pyruvate.
Starting with one molecule of glucose, the “net” products of glycolysis are
6 CO2, 6 H2O, 36 ATP, and 2 citrate.
2 NAD+, 2 H+, 2 pyruvate, 2 ATP, and 2 H2O.
2 NADH, 2 H+, 2 pyruvate, 2 ATP, and 2 H2O.
2 FADH2, 2 pyruvate, 4 ATP, and 2 H2O.
6 CO2, 6 H2O, 2 ATP, and 2 pyruvate.
2 NADH, 2 H+, 2 pyruvate, 2 ATP, and 2 H2O.
In glycolysis, for each molecule of glucose oxidized to pyruvate
2 molecules of ATP are used and 2 molecules of ATP are produced.
2 molecules of ATP are used and 4 molecules of ATP are produced.
4 molecules of ATP are used and 2 molecules of ATP are produced.
2 molecules of ATP are used and 6 molecules of ATP are produced.
6 molecules of ATP are used and 6 molecules of ATP are produced.
2 molecules of ATP are used and 4 molecules of ATP are produced.
During cellular respiration, acetyl CoA accumulates in which location?
mitochondrial matrix
mitochondrial inner membrane
mitochondrial intermembrane space
mitochondrial outer membrane cytosol
mitochondrial matrix
Energy released by the electron transport chain is used to pump H+ ions into which location?
mitochondrial matrix cytosol
mitochondrial intermembrane space
mitochondrial outer membrane
mitochondrial inner membrane
mitochondrial intermembrane space
When hydrogen ions are pumped from the mitochondrial matrix across the inner membrane and into the intermembrane space, the result is the
restoration of the Na+/K+ balance across the membrane.
creation of a proton gradient.
formation of ATP. reduction of NAD+.
lowering of pH in the mitochondrial matrix.
creation of a proton gradient.
Where is ATP synthase located in the mitochondrion?
electron transport chain
cytosol
outer membrane
inner membrane
mitochondrial matrix
Inner membrane
In chemiosmotic phosphorylation, what is the most direct source of energy that is used to convert ADP + Pi to ATP?
energy released as electrons flow through the electron transport system
No external source of energy is required because the reaction is exergonic. energy released from movement of protons through ATP synthase
energy released from ATP synthase pumping hydrogen ions from the mitochondrial matrix
energy released from substrate-level phosphorylation
energy released from movement of protons through ATP synthase
During oxidative phosphorylation, H2O is formed. Where does the oxygen for the synthesis of the water come from?
carbon dioxide (CO2)
lactate (C3H5O3-)
glucose (C6H12O6)
pyruvate (C3H3O3-)
molecular oxygen (O2)
molecular oxygen (O2)
The primary role of oxygen in cellular respiration is to
combine with carbon, forming CO2.
catalyze the reactions of glycolysis.
act as an acceptor for electrons and hydrogen, forming water.
combine with lactate, forming pyruvate.
yield energy in the form of ATP as it is passed down the respiratory chain.
act as an acceptor for electrons and hydrogen, forming water.
Carbon dioxide (CO2) is released during which of the following stages of cellular respiration?
oxidation of pyruvate to acetyl CoA and the citric acid cycle
oxidative phosphorylation and fermentation
glycolysis and the oxidation of pyruvate to acetyl CoA
the citric acid cycle and oxidative phosphorylation
fermentation and glycolysis
oxidation of pyruvate to acetyl CoA and the citric acid cycle
Where are the proteins of the electron transport chain located?
cytosol mitochondrial matrix
mitochondrial intermembrane space
mitochondrial inner membrane
mitochondrial outer membrane
mitochondrial inner membrane
Which metabolic pathway is common to both cellular respiration and fermentation?
oxidative phosphorylation
glycolysis
the citric acid cycle
the oxidation of pyruvate to acetyl CoA
chemiosmosis
glycolysis
In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of
ATP, NADH, and pyruvate.
ATP, pyruvate, and oxygen.
ATP, CO2, and ethanol (ethyl alcohol).
ATP, CO2, and lactate.
ATP, pyruvate, and acetyl CoA.
ATP, CO2, and ethanol (ethyl alcohol).
One function of both alcohol fermentation and lactic acid fermentation is to
reduce FAD+ to FADH2.
reduce FADH2 to FAD+.
oxidize NADH to NAD+.
reduce NAD+ to NADH.
none of the above
oxidize NADH to NAD+
The oxygen consumed during cellular respiration is involved directly in which process or event?
the phosphorylation of ADP to form ATP glycolysis
the oxidation of pyruvate to acetyl CoA
accepting electrons at the end of the electron transport chain
the citric acid cycle
accepting electrons at the end of the electron transport chain
Which of these equations best summarizes photosynthesis?
6 CO2 + 6 O2 → C6H12O6 + 6 H2O
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
C6H12O6 + 6 O2 → 6 CO2 + 12 H2O
H2O → 2 H+ + 1/2 O2 + 2e-
6 CO2 + 6 H2O → C6H12O6 + 6 O2
6 CO2 + 6 H2O → C6H12O6 + 6 O2
Where does the Calvin cycle occur?
C B D A E
E
The light reactions of photosynthesis use _____ and produce _____.
carbon dioxide … oxygen
NADPH … NADP+
water … NADPH
carbon dioxide … sugar
NADPH … oxygen
water … NADPH
Which of these phosphorylates ADP to make ATP?
D E C A B
E
_____ releases energy that is used to pump hydrogen ions from the stroma into the thylakoid compartment.
E B D A C
B
_____ splits water into 1/2 O2, H+, and *e- *.
D A B E C
A
Energized electrons from ____ enter an electron transport chain and are then used to reduce NADP+.
B C D E A
C
Chlorophyll can be found in _____.
B and D
B and C
A and B
A and C
B and E
A and C
Which of the following statements best describes the relationship between photosynthesis and respiration?
Photosynthesis stores energy in complex organic molecules, while respiration releases it.
Respiration is the reversal of the biochemical pathways of photosynthesis.
Respiration is anabolic and photosynthesis is catabolic.
Photosynthesis occurs only in plants and respiration occurs only in animals.
ATP molecules are produced in photosynthesis and used up in respiration.
Photosynthesis stores energy in complex organic molecules, while respiration releases it.
Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?
electrons and H+
CO2 and glucose
ATP and NADPH
ADP, Pi, and NADP+
H2O and O2
ATP and NADPH
In the thylakoid membranes, what is the main role of the antenna pigment molecules?
transfer electrons to ferredoxin and then NADPH
concentrate photons within the stroma
synthesize ATP from ADP and Pi
split water and release oxygen to the reaction-center chlorophyll
harvest photons and transfer light energy to the reaction-center chlorophyll
harvest photons and transfer light energy to the reaction-center chlorophyll
Where does the Calvin cycle take place?
stroma of the chloroplast
chlorophyll molecule
outer membrane of the chloroplast
cytoplasm surrounding the chloroplast
thylakoid membrane
stroma of the chloroplast
Which of the events listed below occur in the light reactions of photosynthesis?
NADP is produced.
light is absorbed and funneled to reaction-center chlorophyll a.
NADPH is reduced to NADP+ carbon dioxide is incorporated into PGA.
ATP is phosphorylated to yield ADP.
light is absorbed and funneled to reaction-center chlorophyll a.
In a plant cell, where are the ATP synthase complexes located?
plasma membrane
thylakoid membrane
thylakoid membrane, plasma membrane and inner mitochondrial membrane
thylakoid membrane and inner mitochondrial membrane
inner mitochondrial membrane
thylakoid membrane and inner mitochondrial membrane
In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from
the stroma to the thylakoid space.
the matrix to the stroma.
the intermembrane space to the matrix.
ATP synthase to NADP+ reductase.
the stroma to the photosystem II.
the stroma to the thylakoid space.
Synthesis of ATP by the chemiosmotic mechanism occurs during
both photosynthesis and respiration.
neither photosynthesis nor respiration.
photorespiration.
photosynthesis.
respiration.
both photosynthesis and respiration.
Generation of proton gradients across membranes occurs during
respiration.
neither photosynthesis nor respiration.
photorespiration.
both photosynthesis and respiration.
photosynthesis.
both photosynthesis and respiration.
For the following question, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produces molecular oxygen (O2)
both the light reactions and the Calvin cycle
the Calvin cycle alone
light reactions alone
neither the light reactions nor the Calvin cycle occurs in the chloroplast but is not part of photosynthesis
light reactions alone
For the following question, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produces NADPH
occurs in the chloroplast but is not part of photosynthesis
the Calvin cycle alone
neither the light reactions nor the Calvin cycle
both the light reactions and the Calvin cycle
light reactions alone
light reactions alone
Carbon fixation involves the addition of carbon dioxide to _____.
RuBP
NADPH
3-PGA
G3P
Rubisco
RuBP
After 3-PGA is phosphorylated, it is reduced by _____.
CO2
ATP
NADP+
ADP
NADPH
NADPH
How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?
8
10
4
6
2
6
In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?
1
4
2
5
3
3
Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?
The light reactions provide the Calvin cycle with oxygen for electron flow, and the Calvin cycle provides the light reactions with water to split.
There is no relationship between the light reactions and the Calvin cycle.
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.
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. The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, Pi, and NADP+ to the light reactions.
The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, Pi, and NADP+ to the light reactions.
Where do the enzymatic reactions of the Calvin cycle take place?
outer membrane of the chloroplast
electron transport chain
thylakoid space
stroma of the chloroplast
thylakoid membranes
stroma of the chloroplast
What is the primary function of the Calvin cycle?
synthesize simple sugars from carbon dioxide
transport RuBP out of the chloroplast
split water and release oxygen
use NADPH to release carbon dioxide
use ATP to release carbon dioxide
synthesize simple sugars from carbon dioxide
For the following question, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Requires ATP
occurs in the chloroplast but is not part of photosynthesis
neither the light reactions nor the Calvin cycle
the Calvin cycle alone
both the light reactions and the Calvin cycle
light reactions alone
the Calvin cycle alone
For the following question, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produces NADH
occurs in the chloroplast but is not part of photosynthesis
the Calvin cycle alone
both the light reactions and the Calvin cycle
light reactions alone
neither the light reactions nor the Calvin cycle
neither the light reactions nor the Calvin cycle
For the following question, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produces three-carbon sugars
the Calvin cycle alone
occurs in the chloroplast but is not part of photosynthesis
light reactions alone
both the light reactions and the Calvin cycle
neither the light reactions nor the Calvin cycle
the Calvin cycle alone
For the following question, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Requires CO2
neither the light reactions nor the Calvin cycle
the Calvin cycle alone
both the light reactions and the Calvin cycle
light reactions alone
occurs in the chloroplast but is not part of photosynthesis
the Calvin cycle alone
For the following question, compare the light reactions with the Calvin cycle of photosynthesis in plants.
Requires glucose
both the light reactions and the Calvin cycle
neither the light reactions nor the Calvin cycle
light reactions alone
the Calvin cycle alone
occurs in the chloroplast but is not part of photosynthesis
neither the light reactions nor the Calvin cycle
