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Campbell Biology, 10e (Reece)
Chapter 7 Membrane
Structure and Function
1)
For a protein to be an integral membrane protein, it would have to be _____.
A)
hydrophilic
B)
hydrophobic
C)
amphipathic, with at least one hydrophobic region
D)
exposed on only one surface of the membrane
2)
You have a planar bilayer with equal amounts of saturated and unsaturated
phospholipids. After testing the permeability of this membrane to glucose, you
increase the proportion of unsaturated phospholipids in the bilayer. What will
happen to the membrane's permeability to glucose?
A)
Permeability to glucose will increase.
B)
Permeability to glucose will decrease.
C)
Permeability to glucose will stay the same.
D)
You cannot predict the outcome. You simply have to make the measurement.
3)
According to the fluid mosaic model of cell membranes, phospholipids _____.
A)
can move laterally along the plane of the membrane
B)
frequently flip-flop from one side of the membrane to the other
C)
occur in an uninterrupted bilayer, with membrane proteins restricted to the
surface of the membrane
D)
have hydrophilic tails in the interior of the membrane
4)
The membranes of winter wheat are able to remain fluid when it is extremely
cold by _____.
A)
increasing the percentage of unsaturated phospholipids in the membrane
B)
increasing the percentage of cholesterol molecules in the membrane
C)
decreasing the number of hydrophobic proteins in the membrane
D)
cotransport of glucose and hydrogen
5)
Some regions of the plasma membrane, called lipid rafts, have a higher
concentration of cholesterol molecules. At higher temperatures, these regions
_____.
A)
are more fluid than the surrounding membrane
B)
are less fluid than the surrounding membrane
C)
detach from the plasma membrane and clog arteries
D)
have higher rates of lateral diffusion of lipids and proteins into and out of
these regions
6)
Singer and Nicolson's fluid mosaic model of the membrane proposed that
membranes_____.
A)
are a phospholipid bilayer between two layers of hydrophilic proteins
B)
are a single layer of phospholipids and proteins
C)
consist of protein molecules embedded in a fluid bilayer of phospholipids
D)
consist of a mosaic of polysaccharides and proteins
7)
An animal cell lacking oligosaccharides on the external surface of its plasma
membrane would likely be impaired in which function?
A)
transporting ions against an electrochemical gradient
B)
cell-cell recognition
C)
attaching the plasma membrane to the cytoskeleton
D)
establishing a diffusion barrier to charged molecules
8)
Which of these are NOT embedded in the hydrophobic portion of the lipid bilayer
at all?
A)
transmembrane proteins
B)
integral proteins
C)
peripheral proteins
D)
All of these are embedded in the hydrophobic portion of the lipid bilayer.
9)
Why are lipids and proteins free to move laterally in membranes?
A)
The interior of the membrane is filled with liquid water.
B)
Lipids and proteins repulse each other in the membrane.
C)
Hydrophilic portions of the lipids are in the interior of the membrane.
D)
There are only weak hydrophobic interactions in the interior of the membrane.
For
the following questions, match the labeled component of the cell membrane in
the figure with its description.
10)
Which component is a peripheral protein?
A)
A
B)
B
C)
C
D)
D
11)
Which component is cholesterol?
A)
B
B)
C
C)
D
D)
E
12)
Which component is a protein fiber of the extracellular matrix?
A)
A
B)
B
C)
C
D)
E
13)
Which component is a microfilament (actin filament) of the cytoskeleton?
A)
A
B)
B
C)
C
D)
D
14)
Which component is a glycolipid?
A)
A
B)
B
C)
C
D)
E
15)
Cell membranes are asymmetrical. Which of the following statements is the most
likely explanation for the membrane's asymmetrical nature?
A)
Since the cell membrane forms a border between one cell and another in tightly
packed tissues such as epithelium, the membrane must be asymmetrical
B)
Since cell membranes communicate signals from one organism to another, the cell
membranes must be asymmetrical.
C)
The two sides of a cell membrane face different environments and carry out
different functions.
D) Proteins only function on the cytoplasmic
side of the cell membrane, which results in the membrane's asymmetrical nature.
16)
In what way do the membranes of a eukaryotic cell vary?
A) Phospholipids are found only in
certain membranes.
B) Certain proteins are unique to each
membrane.
C) Only certain membranes of the cell
are selectively permeable.
D) Some membranes have hydrophobic
surfaces exposed to the cytoplasm, while others have hydrophilic surfaces
facing the cytoplasm.
17)
Which of the following is a reasonable explanation for why unsaturated fatty
acids help keep a membrane more fluid at lower temperatures?
A)
The double bonds form kinks in the fatty acid tails, preventing adjacent lipids
from packing tightly.
B)
Unsaturated fatty acids have a higher cholesterol content and, therefore, more
cholesterol in membranes.
C)
Unsaturated fatty acids are more polar than saturated fatty acids.
D)
The double bonds block interaction among the hydrophilic head groups of the
lipids.
18)
What kinds of molecules pass through a cell membrane most easily?
A)
large and hydrophobic
B)
small and hydrophobic
C)
large polar
D)
ionic
19)
Which of the following most accurately describes selective permeability?
A)
An input of energy is required for transport.
B)
Lipid-soluble molecules pass through a membrane.
C)
There must be a concentration gradient for molecules to pass through a
membrane.
D)
Only certain molecules can cross a cell membrane.
20)
Which of the following is a characteristic feature of a carrier protein in a
plasma membrane?
A)
It exhibits a specificity for a particular type of molecule.
B)
It requires the expenditure of cellular energy to function.
C)
It works against diffusion.
D)
It has no hydrophobic regions.
21)
Which of the following would likely move through the lipid bilayer of a plasma
membrane most rapidly?
A)
CO2
B)
an amino acid
C)
glucose
D)
K+
22)
Which of the following allows water to move much faster across cell membranes?
A)
the sodium-potassium pump
B)
ATP
C)
peripheral proteins
D)
aquaporins
23)
You are working on a team that is designing a new drug. For this drug to work,
it must enter the cytoplasm of specific target cells. Which of the following
would be a factor that determines whether the molecule selectively enters the
target cells?
A)
hydrophobicity of the drug molecule
B)
lack of charge on the drug molecule
C)
similarity of the drug molecule to other molecules transported by the target
cells
D)
lipid composition of the target cells' plasma membrane
24)
Diffusion _____.
A)
is very rapid over long distances
B)
requires an expenditure of energy by the cell
C)
is a passive process in which molecules move from a region of higher
concentration to a region of lower concentration
D)
requires integral proteins in the cell membrane
25)
Which of the following processes includes all others?
A) osmosis
B) facilitated diffusion
C) passive transport
D) transport of an ion down its
electrochemical gradient
26)
When a cell is in equilibrium with its environment, which of the following
occurs for substances that can diffuse through the cell?
A)
There is random movement of substances into and out of the cell.
B)
There is directed movement of substances into and out of the cell.
C)
There is no movement of substances into and out of the cell.
D)
All movement of molecules is directed by active transport.
27)
Which of the following is true of osmosis?
A)
Osmosis only takes place in red blood cells.
B)
Osmosis is an energy-demanding or "active" process.
C)
In osmosis, water moves across a membrane from areas of lower solute
concentration to areas of higher solute concentration.
D)
In osmosis, solutes move across a membrane from areas of lower water
concentration to areas of higher water concentration.
The
solutions in the two arms of this U-tube are separated by a membrane that is
permeable to water and glucose but not to sucrose. Side A is half-filled with a
solution of 2 M sucrose and 1 M glucose. Side B is half-filled
with 1 M sucrose and 2 M glucose. Initially, the liquid levels on
both sides are equal.
28)
Refer t o the figure. Initially, in terms of tonicity, the solution in side A
with respect to the solution in side B is _____.
A)
hypotonic
B)
isotonic
C)
saturated
D)
hypertonic
29)
Refer to the figure. After the system reaches equilibrium, what changes are
observed?
A)
The molarity of sucrose is higher than that of glucose on side A.
B)
The water level is higher in side A than in side B.
C)
The water level is unchanged.
D)
The water level is higher in side B than in side A.
30)
A patient was involved a serious accident and lost a large quantity of blood.
In an attempt to replenish body fluids, distilled water—equal to the volume of
blood lost—is added to the blood directly via one of his veins. What will be
the most probable result of this transfusion?
A)
The patient's red blood cells will shrivel up because the blood has become
hypotonic compared to the cells.
B)
The patient's red blood cells will swell and possibly burst because the blood
has become hypotonic compared to the cells.
C)
The patient's red blood cells will shrivel up because the blood has become
hypertonic compared to the cells.
D)
The patient's red blood cells will burst because the blood has become
hypertonic compared to the cells.
The
solutions in the arms of a U-tube are separated at the bottom of the tube by a
selectively permeable membrane. The membrane is permeable to sodium chloride
but not to glucose. Side A is filled with a solution of 0.4 M glucose
and 0.5 M sodium chloride (NaCl), and side B is filled with a solution
containing 0.8 M glucose and 0.4 M sodium chloride. Initially,
the volume in both arms is the same..
31)
Refer to the figure. At the beginning of the experiment,
A)
side A is hypertonic to side B.
B)
side A is hypotonic to side B.
C)
side A is hypertonic to side B with respect to glucose.
D)
side A is hypotonic to side B with respect to NaCl.
32)
Refer to the figure. If you examine side A after three days, you should find
_____.
A)
a decrease in the concentration of NaCl and glucose and an increase in the
water level
B)
a decrease in the concentration of NaCl, an increase in water level, and no
change in the concentration of glucose
C)
a decrease in the concentration of NaCl and a decrease in the water level
D)
no change in the concentration of NaCl and glucose and an increase in the water
level
Five
dialysis bags constructed of membrane, which is permeable to water and
impermeable to sucrose, were filled with various concentrations of sucrose and
then placed in separate beakers containing an initial concentration of 0.6 M
sucrose solution. At 10-minute intervals, the bags were massed (weighed) and
the percent change in mass of each bag was graphed.
33)
Which line in the graph represents the bag that contained a solution isotonic
to the 0.6 M solution at the beginning of the experiment?
A)
A
B)
B
C)
C
D)
D
34)
Which line in the graph represents the bag with the highest initial
concentration of sucrose?
A)
A
B)
B
C)
C
D)
D
35)
Which line or lines in the graph represent(s) bags that contain a solution that
is hypertonic at 50 minutes?
A)
A and B
B)
B
C)
D
D)
D and E
36)
Celery stalks that are immersed in fresh water for several hours become stiff.
Similar stalks left in a 0.15 M salt solution become limp. From this we
can deduce that the fresh water_____.
A)
and the salt solution are both hypertonic to the cells of the celery stalks
B)
is hypotonic and the salt solution is hypertonic to the cells of the celery
stalks
C)
is hypertonic and the salt solution is hypotonic to the cells of the celery
stalks
D)
is isotonic and the salt solution is hypertonic to the cells of the celery
stalks
37)
What will happen to a red blood cell (RBC), which has an internal ion
concentration of about 0.9 percent, if it is placed into a beaker of pure
water?
A)
The cell would shrink because the water in the beaker is hypotonic relative to
the cytoplasm of the RBC.
B)
The cell would shrink because the water in the beaker is hypertonic relative to
the cytoplasm of the RBC.
C)
The cell would swell because the water in the beaker is hypotonic relative to
the cytoplasm of the RBC.
D)
The cell will remain the same size because the solution outside the cell is
isotonic.
38)
Which of the following statements correctly describes the normal tonicity
conditions for typical plant and animal cells? The animal cell is in _____.
A)
a hypotonic solution, and the plant cell is in an isotonic solution
B)
an isotonic solution, and the plant cell is in a hypertonic solution
C)
a hypertonic solution, and the plant cell is in an isotonic solution
D)
an isotonic solution, and the plant cell is in a hypotonic solution
39)
In which of the following would there be the greatest need for osmoregulation?
A)
an animal connective tissue cell bathed in isotonic body fluid
B)
a salmon moving from a river into an ocean
C)
a red blood cell surrounded by plasma
D)
a plant being grown hydroponically in a watery mixture of designated nutrients
40)
When a plant cell, such as one from a rose stem, is submerged in a very
hypotonic solution, what is likely to occur?
A)
The cell will burst.
B)
Plasmolysis will shrink the interior.
C)
The cell will become flaccid.
D)
The cell will become turgid.
41)
A sodium-potassium pump _____.
A)
moves three potassium ions out of a cell and two sodium ions into a cell while
producing an ATP for each cycle
B)
move three sodium ions out of a cell and two potassium ions into a cell while
consuming an ATP for each cycle
C)
moves three potassium ions out of a cell and two sodium ions into a cell while
consuming 2 ATP in each cycle
D)
move three sodium ions out of a cell and two potassium ions into a cell and
generates an ATP in each cycle
42)
The sodium-potassium pump is called an electrogenic pump because it _____.
A)
pumps equal quantities of Na+ and K+ across the membrane
B)
contributes to the membrane potential
C)
ionizes sodium and potassium atoms
D)
is used to drive the transport of other molecules against a concentration
gradient
43)
Which of the following membrane activities requires energy from ATP?
A)
facilitated diffusion of chloride ions across the membrane through a chloride
channel
B)
movement of Na+ ions from a lower concentration in a mammalian
cell to a higher concentration in the extracellular fluid
C)
movement of glucose molecules into a bacterial cell from a medium containing a
higher concentration of glucose than inside the cell
D)
movement of carbon dioxide out of a paramecium
44)
The voltage across a membrane is called the _____.
A)
chemical gradient
B)
membrane potential
C)
osmotic potential
D)
electrochemical gradient
45)
Ions diffuse across membranes through specific ion channels down _____.
A)
their chemical gradients
B)
their concentration gradients
C)
the electrical gradients
D)
their electrochemical gradients
46)
Which of the following would increase the electrochemical gradient across a
membrane?
A)
a sucrose-proton cotransporter
B)
a proton pump
C)
a potassium channel
D)
both a proton pump and a potassium channel
47)
The phosphate transport system in bacteria imports phosphate into the cell even
when the concentration of phosphate outside the cell is much lower than the
cytoplasmic phosphate concentration. Phosphate import depends on a pH gradient
across the membrane—more acidic outside the cell than inside the cell.
Phosphate transport is an example of _____.
A)
passive diffusion
B)
facilitated diffusion
C)
active transport
D)
cotransport
48)
In some cells, there are many ion electrochemical gradients across the plasma
membrane even though there are usually only one or two proton pumps present in
the membrane. The gradients of the other ions are most likely accounted for by
_____.
A)
cotransport proteins
B)
ion channels
C)
pores in the plasma membrane
D)
passive diffusion across the plasma membrane
49)
Which of the following is most likely true of a protein that cotransports
glucose and sodium ions into the intestinal cells of an animal?
A)
Sodium and glucose compete for the same binding site in the cotransporter.
B)
Glucose entering the cell down its concentration gradient provides energy for
uptake of sodium ions against the electrochemical gradient.
C)
Sodium ions can move down their electrochemical gradient through the
cotransporter whether or not glucose is present outside the cell.
D)
A substance that blocks sodium ions from binding to the cotransport protein
will also block the transport of glucose.
50)
Proton pumps are used in various ways by members of every domain of organisms:
Bacteria, Archaea, and Eukarya. What does this most probably mean?
A)
Proton gradients across a membrane were used by cells that were the common
ancestor of all three domains of life.
B)
The high concentration of protons in the ancient atmosphere must have
necessitated a pump mechanism.
C)
Cells of each domain evolved proton pumps independently when oceans became more
acidic.
D)
Proton pumps are necessary to all cell membranes.
51)
Several epidemic microbial diseases of earlier centuries incurred high death
rates because they resulted in severe dehydration due to vomiting and diarrhea.
Today they are usually not fatal because we have developed which of the
following?
A)
antiviral medications that are efficient and work well with most viruses
B)
intravenous feeding techniques
C)
medications to slow blood loss
D)
hydrating drinks with high concentrations of salts and glucose
52)
The force driving simple diffusion is _____, while the energy source for active
transport is _____.
A)
the concentration gradient; ADP
B)
the concentration gradient; ATP
C)
transmembrane pumps; electron transport
D)
phosphorylated protein carriers; ATP
53)
An organism with a cell wall would most likely be unable to take in materials
through _____.
A)
osmosis
B)
active transport
C)
phagocytosis
D)
facilitated diffusion
54)
White blood cells engulf bacteria using _____.
A)
phagocytosis
B)
pinocytosis
C)
osmosis
D)
receptor-mediated exocytosis
55)
Familial hypercholesterolemia is characterized by _____.
A)
defective LDL receptors on the cell membranes
B)
poor attachment of the cholesterol to the extracellular matrix of cells
C)
a poorly formed lipid bilayer that cannot incorporate cholesterol into cell
membranes
D)
inhibition of the cholesterol active transport system in red blood cells
56)
The difference between pinocytosis and receptor-mediated endocytosis is that
_____.
A)
pinocytosis brings only water molecules into the cell, but receptor-mediated
endocytosis brings in other molecules as well.
B)
pinocytosis increases the surface area of the plasma membrane, whereas
receptor-mediated endocytosis decreases the plasma membrane surface area.
C)
pinocytosis is nonselective in the molecules it brings into the cell, whereas
receptor-mediated endocytosis offers more selectivity.
D)
pinocytosis can concentrate substances from the extracellular fluid, but
receptor-mediated endocytosis cannot.
57)
In receptor-mediated endocytosis, receptor molecules initially project to the
outside of the cell. Where do they end up after endocytosis?
A)
on the outside of vesicles
B)
on the inside surface of the cell membrane
C)
on the inside surface of the vesicle
D)
on the outer surface of the nucleus
58)
A bacterium engulfed by a white blood cell through phagocytosis will be
digested by enzymes contained in _____.
A)
lysosomes
B)
Golgi vesicles
C)
vacuoles
D)
secretory vesicles
Use
the paragraph and accompanying figure to answer the following questions.
Human
immunodeficiency virus (HIV) infects cells that have both CD4 and CCR5 cell
surface molecules. The viral nucleic acid molecules are enclosed in a protein
capsid, and the protein capsid is itself contained inside an envelope
consisting of a lipid bilayer membrane and viral glycoproteins. One hypothesis
for viral entry into cells is that binding of HIV membrane glycoproteins to CD4
and CCR5 initiates fusion of the HIV membrane with the plasma membrane,
releasing the viral capsid into the cytoplasm. An alternative hypothesis is
that HIV gains entry into the cell via receptor-mediated endocytosis, and
membrane fusion occurs in the endocytotic vesicle. To test these alternative
hypotheses for HIV entry, researchers labeled the lipids on the HIV membrane
with a red fluorescent dye.
59)
In an HIV-infected cell producing HIV virus particles, the viral glycoprotein
is expressed on the plasma membrane. How do the viral glycoproteins get to the
plasma membrane? They are synthesized _____.
A)
on ribosomes on the plasma membrane
B)
by ribosomes in the rough ER and arrive at the plasma membrane in the membrane
of secretory vesicles
C)
on free cytoplasmic ribosomes and then inserted into the plasma membrane
D)
by ribosomes in the rough ER, secreted from the cell, and inserted into the plasma
membrane from the outside
60)
What would be observed by live-cell fluorescence microscopy immediately after
HIV entry if HIV is endocytosed first, and then later fuses with the
endocytotic vesicle membrane?
A)
A spot of red fluorescence will be visible on the infected cell's plasma
membrane, marking the site of membrane fusion and HIV entry.
B)
The red fluorescent dye-labeled lipids will appear in the infected cell's
interior.
C)
A spot of red fluorescence will diffuse in the infected cell's cytoplasm.
D)
A spot of red fluorescence will remain outside the cell after delivering the
viral capsid.
61)
Three lab groups carried out an experiment to identify the correct molarities
for five solutions. Each unknown contained one of the following sucrose
concentrations: 0.0 M, 0.2 M, 0.4 M, 0.6 M, 0.8 M, and 1.0 M. Each data entry represents the average
of 3 sample replications of 1 cm3 sweet
potato cubes expressed as percent change in mass after an overnight (24 hr)
soak in the unknown solutions. From the data given, which statement most
accurately describes what is occurring in response to a particular unknown
solution.
A)
Unknown solution E contains the highest concentration of sucrose and the change
in mass is due to the active transport of sucrose into the cell in exchange for
water molecules.
B)
Osmosis of water molecules from unknown solution A likely caused the increase
in mass observed.
C)
Passive transport of sucrose out of the potato cells explains the change in
mass observed for unknown solution F.
D)
Unknown solution C represents a sucrose molarity slightly lower than the
molarity of sweet potato cells, thus water is transported out of the cells.
Campbell Biology, 10e (Reece)
Chapter 8 An
Introduction to Metabolism
1)
Which of the following is true of metabolism in its entirety in all organisms?
A)
Metabolism depends on a constant supply of energy from food.
B)
Metabolism uses all of an organism's resources.
C)
Metabolism consists of all the energy transformation reactions in an organism.
D)
Metabolism manages the increase of entropy in an organism.
2)
Which of the following is an example of potential rather than kinetic energy?
A)
water rushing over Niagara Falls
B)
light flashes emitted by a firefly
C)
a molecule of glucose
D)
a crawling beetle foraging for food
3)
Most cells cannot harness heat to perform work because _____.
A) heat is not a form of energy
B) temperature is usually uniform throughout
a cell
C) heat can never be used to do work
D) heat must remain constant during work
4)
Which of the following involves a decrease in entropy?
A)
condensation reactions
B)
reactions that separate monomers
C)
depolymerization reactions
D)
hydrolysis reactions
5)
Which term most precisely describes the cellular process of breaking down large
molecules into smaller ones?
A)
catabolism (catabolic pathways)
B)
metabolism
C)
anabolism (anabolic pathways)
D)
dehydration
6)
Anabolic pathways _____.
A)
are usually highly spontaneous chemical reactions
B)
consume energy to build up polymers from monomers
C)
release energy as they degrade polymers to monomers
D)
consume energy to decrease the entropy of the organism and its environment
7)
Which of the following is a statement of the first law of thermodynamics?
A)
Energy cannot be created or destroyed.
B)
The entropy of the universe is decreasing.
C)
The entropy of the universe is constant.
D)
Energy cannot be transferred or transformed.
8)
For living organisms, which of the following is an important consequence of the
first law of thermodynamics?
A)
The energy content of an organism is constant.
B)
The organism ultimately must obtain all of the necessary energy for life from
its environment.
C)
The entropy of an organism decreases with time as the organism grows in
complexity.
D)
Organisms grow by converting energy into organic matter.
9)
Living organisms increase in complexity as they grow, resulting in a decrease
in the entropy of an organism. How does this relate to the second law of
thermodynamics?
A)
Living organisms do not obey the second law of thermodynamics, which states
that entropy must increase with time.
B)
Life obeys the second law of thermodynamics because the decrease in entropy as
the organism grows is exactly balanced by an increase in the entropy of the
universe.
C)
As a consequence of growing, organisms cause a greater increase in entropy in
their environment than the decrease in entropy associated with their growth.
D)
Living organisms are able to transform energy into entropy.
10)
Which of the following statements is a logical consequence of the second law of
thermodynamics?
A)
If the entropy of a system increases, there must be a corresponding decrease in
the entropy of the universe.
B)
If there is an increase in the energy of a system, there must be a
corresponding decrease in the energy of the rest of the universe.
C)
Every chemical reaction must increase the total entropy of the universe.
D)
Energy can be transferred or transformed, but it cannot be created or
destroyed.
11)
Which of the following statements is representative of the second law of
thermodynamics?
A)
Conversion of energy from one form to another is always accompanied by some
gain of free energy.
B)
Without an input of energy, organisms would tend toward decreasing entropy.
C)
Cells require a constant input of energy to maintain their high level of
organization.
D)
Every energy transformation by a cell decreases the entropy of the universe.
12)
Which of the following types of reactions would decrease the entropy within a
cell?
A)
anabolic reactions
B)
hydrolysis
C)
digestion
D)
catabolic reactions
13)
Biological evolution of life on Earth, from simple prokaryote-like cells to
large, multicellular eukaryotic organisms, _____.
A)
has occurred in accordance with the laws of thermodynamics
B)
has caused an increase in the entropy of the planet
C)
has been made possible by expending Earth's energy resources
D)
has occurred in accordance with the laws of thermodynamics, by expending
Earth's energy resources and causing an increase in the entropy of the planet
14)
The mathematical expression for the change in free energy of a system is ΔG
=ΔH - TΔS. Which of the following is (are) correct?
A)
ΔS is the change in enthalpy, a measure of randomness.
B)
ΔH is the change in entropy, the energy available to do work.
C)
ΔG is the change in free energy.
D)
T is the temperature in degrees Celsius.
15)
A system at chemical equilibrium _____.
A)
consumes energy at a steady rate
B)
releases energy at a steady rate
C)
has zero kinetic energy
D)
can do no work
16)
Which of the following is true for all exergonic reactions?
A)
The products have more total energy than the reactants.
B)
The reaction proceeds with a net release of free energy.
C)
The reaction goes only in a forward direction: all reactants will be converted
to products, but no products will be converted to reactants.
D)
A net input of energy from the surroundings is required for the reactions to
proceed.
17)
A chemical reaction that has a positive ΔG is best described as _____.
A)
endergonic
B)
enthalpic
C)
spontaneous
D)
exergonic
18)
Chemical equilibrium is relatively rare in living cells. An example of a
reaction at chemical equilibrium in a cell would be _____.
A)
one in which the free energy at equilibrium is higher than the energy content
at any point away from equilibrium
B)
one in which the entropy change in the reaction is just balanced by an opposite
entropy change in the cell's surroundings
C)
an endergonic reaction in an active metabolic pathway where the energy for that
reaction is supplied only by heat from the environment
D)
a chemical reaction in which both the reactants and products are not being
produced or used in any active metabolic pathway at that time in the cell
19)
Choose the pair of terms that correctly completes this sentence: Catabolism is
to anabolism as _____ is to _____.
A) exergonic; spontaneous
B) exergonic;
endergonic
C) free energy;
entropy
D) work; energy
20)
In solution, why do hydrolysis reactions occur more readily than condensation
reactions?
A)
Hydrolysis increases entropy and is exergonic.
B)
Hydrolysis raises G, or Gibbs free energy.
C)
Hydrolysis decreases entropy and is exergonic.
D)
Hydrolysis increases entropy and is endergonic.
21)
Why is ATP an important molecule in metabolism?
A)
Its hydrolysis provides an input of free energy for exergonic reactions.
B)
It provides energy coupling between exergonic and endergonic reactions.
C)
Its terminal phosphate group contains a strong covalent bond that, when
hydrolyzed, releases free energy.
D)
Its terminal phosphate bond has higher energy than the other two phosphate
bonds.
22)
When 10,000 molecules of ATP are hydrolyzed to ADP and i in a test
tube, about half as much heat is liberated as when a cell hydrolyzes the same
amount of ATP. Which of the following is the best explanation for this
observation?
i in a test
tube, about half as much heat is liberated as when a cell hydrolyzes the same
amount of ATP. Which of the following is the best explanation for this
observation?
A)
Cells are open systems, but a test tube is an isolated system.
B)
Cells are less efficient at heat production than nonliving systems.
C)
The reaction in cells must be catalyzed by enzymes, but the reaction in a test
tube does not need enzymes.
D)
Reactant and product concentrations in the test tube are different from those
in the cell.
23)
Which of the following is most similar in structure to ATP?
A)
a pentose sugar
B)
a DNA nucleotide
C)
an RNA nucleotide
D)
an amino acid with three phosphate groups attached
24)
Catabolic pathways _____.
A)
combine molecules into more energy-rich molecules
B)
supply energy, primarily in the form of ATP, for the cell's work
C)
are endergonic
D)
are spontaneous and do not need enzyme catalysis
25)
When chemical, transport, or mechanical work is done by an organism, what
happens to the heat generated?
A)
It is used to power yet more cellular work.
B)
It is used to store energy as more ATP.
C)
It is used to generate ADP from nucleotide precursors.
D)
It is lost to the environment.
26)
When ATP releases some energy, it also releases inorganic phosphate. What
happens to the inorganic phosphate in the cell?
A)
It is secreted as waste.
B)
It is used only to regenerate more ATP.
C)
It may be used to form a phosphorylated intermediate.
D)
It enters the nucleus and affects gene expression.
27)
A number of systems for pumping ions across membranes are powered by ATP. Such
ATP-powered pumps are often called ATPases, although they do not often
hydrolyze ATP unless they are simultaneously transporting ions. Because small
increases in calcium ions in the cytosol can trigger a number of different
intracellular reactions, cells keep the cytosolic calcium concentration quite
low under normal conditions, using ATP-powered calcium pumps. For example,
muscle cells transport calcium from the cytosol into the membranous system
called the sarcoplasmic reticulum (SR). If a resting muscle cell's cytosol has
a free calcium ion concentration of 10-7 while the concentration in the SR is 10-2, then how is
the ATPase acting?
A)
ATPase activity must be powering an inflow of calcium from the outside of the
cell into the SR.
B)
ATPase activity must be transferring i to the SR
to enable this to occur.
i to the SR
to enable this to occur.
C)
ATPase activity must be pumping calcium from the cytosol to the SR against the
concentration gradient.
D)
ATPase activity must be opening a channel for the calcium ions to diffuse back
into the SR along the concentration gradient.
28)
Which of the following is the most correct interpretation of the figure?
A)
Energy from catabolism can be used directly for performing cellular work.
B)
ADP + i are a set
of molecules that store energy for catabolism.
i are a set
of molecules that store energy for catabolism.
C)
ATP is a molecule that acts as an intermediary to store energy for cellular
work.
D)
i acts as a
shuttle molecule to move energy from ATP to ADP.
i acts as a
shuttle molecule to move energy from ATP to ADP.
29)
How do cells use the ATP cycle shown in the figure?
A)
Cells use the cycle to recycle ADP and phosphate.
B)
Cells use the cycle to recycle energy released by ATP hydrolysis.
C)
Cells use the cycle to recycle ADP, phosphate, and the energy released by ATP
hydrolysis.
D)
Cells use the cycle primarily to generate heat.
30)
Which of the following is true of enzymes?
A)
Enzyme function is increased if the 3- D structure or conformation of an enzyme
is altered.
B)
Enzyme function is independent of physical and chemical environmental factors
such as pH and temperature.
C)
Enzymes increase the rate of chemical reaction by lowering activation energy
barriers.
D)
Enzymes increase the rate of chemical reaction by providing activation energy
to the substrate.
31)
Which of the following is true when comparing an uncatalyzed reaction to the
same reaction with a catalyst?
A)
The catalyzed reaction will be slower.
B)
The catalyzed reaction will have the same ∆G.
C)
The catalyzed reaction will have higher activation energy.
D)
The catalyzed reaction will consume all of the catalyst.
32)
The lock-and-key analogy for enzymes applies to the specificity of enzymes
_____.
A)
as they form their tertiary and quaternary structure
B)
binding to their substrate
C)
interacting with water
D)
interacting with ions
33)
You have discovered an enzyme that can catalyze two different chemical
reactions. Which of the following is most likely to be correct?
A)
The enzyme contains α-helices and β-pleated sheets.
B)
The enzyme is subject to competitive inhibition and allosteric regulation.
C)
Two types of allosteric regulation occur: The binding of one molecule activates
the enzyme, while the binding of a different molecule inhibits it.
D)
Either the enzyme has two distinct active sites or the reactants involved in
the two reactions are very similar in size and shape.
34)
Reactants capable of interacting to form products in a chemical reaction must
first overcome a thermodynamic barrier known as the reaction's _____.
A)
entropy
B)
activation energy
C)
equilibrium point
D)
free-energy content
35)
During a laboratory experiment, you discover that an enzyme-catalyzed reaction
has a ∆G of -20 kcal/mol. If you double the amount of enzyme in the
reaction, what will be the ∆G for the new reaction?
A)
-40 kcal/mol
B)
-20 kcal/mol
C)
0 kcal/mol
D)
+20 kcal/mol
36)
The active site of an enzyme is the region that _____.
A)
binds allosteric regulators of the enzyme
B)
is involved in the catalytic reaction of the enzyme
C)
binds noncompetitive inhibitors of the enzyme
D)
is inhibited by the presence of a coenzyme or a cofactor
37)
According to the induced fit hypothesis of enzyme catalysis, _____.
A)
the binding of the substrate depends on the shape of the active site
B)
some enzymes change their structure when activators bind to the enzyme
C)
the binding of the substrate changes the shape of the enzyme's active site
D)
the active site creates a microenvironment ideal for the reaction
38)
Increasing the substrate concentration in an enzymatic reaction could overcome
which of the following?
A)
the need for a coenzyme
B)
allosteric inhibition
C)
competitive inhibition
D)
insufficient cofactors
39)
Zinc, an essential trace element for most organisms, is present in the active
site of the enzyme carboxypeptidase. The zinc most likely functions as _____.
A)
a noncompetitive inhibitor of the enzyme
B)
an allosteric activator of the enzyme
C)
a cofactor necessary for enzyme activity
D)
a coenzyme derived from a vitamin
40)
A noncompetitive inhibitor decreases the rate of an enzyme reaction by _____.
A)
binding at the active site of the enzyme
B)
changing the shape of the enzyme's active site
C)
changing the free energy change of the reaction
D)
acting as a coenzyme for the reaction
41)
You collect data on the effect of pH on the function of the enzyme catalase in
human cells. Which of the following graphs would you expect?
A)
B)
C)
D)
42)
How might a change of one amino acid at a site, distant from the active site of
an enzyme, alter an enzyme's substrate specificity?
A)
by changing the enzyme's stability
B)
by changing the shape of an enzyme
C)
by changing the enzyme's pH optimum
D)
An amino acid change away from the active site cannot alter the enzyme's
substrate specificity.
43)
For the enzyme- catalyzed reaction shown in the figure, if the initial reactant
concentration is 1.0 micromolar, which of these treatments will cause the
greatest increase in the rate of the reaction?
A)
doubling the activation energy needed
B)
cooling the reaction by 10°C
C)
doubling the enzyme concentration
D)
increasing the concentration of reactants to 10.0 micromolar, while reducing
the concentration of enzyme by 1/2
Rate
of an enzyme-catalyzed reaction as a function of varying reactant
concentration,
with the concentration of enzyme constant.
44)
In the figure, why does the reaction rate plateau at higher reactant
concentrations?
A)
Feedback inhibition by product occurs at high reactant concentrations.
B)
Most enzyme molecules are occupied by substrate at high reactant
concentrations.
C)
The reaction nears equilibrium at high reactant concentrations.
D)
The rate of the reverse reaction increases with reactant concentration.
Activity
of various enzymes at various temperatures (a) and at various pH (b).
45)
Which curves on the graphs may represent the temperature and pH profiles of an
enzyme taken from a bacterium that lives in a mildly alkaline hot springs at
temperatures of 70°C or higher?
A)
curves 1 and 5
B)
curves 2 and 5
C)
curves 3 and 4
D)
curves 3 and 5
46)
Which temperature and pH profile curves on the graphs were most likely
generated from analysis of an enzyme from a human stomach where conditions are
strongly acid?
A)
curves 1 and 4
B)
curves 1 and 5
C)
curves 2 and 4
D)
curves 3 and 4
The
following questions are based on the reaction A + B ↔ C + D
shown in the accompanying figure.
47)
Which of the following terms best describes the forward reaction in the figure?
A)
endergonic, ∆G > 0
B)
exergonic, ∆G < 0
C)
endergonic, ∆G < 0
D)
exergonic, ∆G > 0
48)
Which of the following in the figure would be the same in either an
enzyme-catalyzed or a noncatalyzed reaction?
A)
a
B)
b
C)
c
D)
d
49)
Which of the following represents the activation energy required for the
enzyme-catalyzed reaction in the figure?
A)
a
B)
b
C)
c
D)
d
Use
the following information to answer the questions below.
Succinate
dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction
is inhibited by malonic acid, which resembles succinate but cannot be acted
upon by succinate dehydrogenase. Increasing the ratio of succinate to malonic
acid reduces the inhibitory effect of malonic acid.
50)
Based on this information, which of the following is correct?
A)
Succinate dehydrogenase is the enzyme, and fumarate is the substrate.
B)
Succinate dehydrogenase is the enzyme, and malonic acid is the substrate.
C)
Succinate is the substrate, and fumarate is the product.
D)
Fumarate is the product, and malonic acid is a noncompetitive inhibitor.
51)
What is malonic acid's role with respect to succinate dehydrogenase? Malonic
acid _____.
A)
is a competitive inhibitor
B)
blocks the binding of fumarate
C)
is a noncompetitive inhibitor
D)
is an allosteric regulator
52)
HIV is the virus that causes AIDS. In the mid-1990s, researchers discovered an
enzyme in HIV called protease. Once the enzyme's structure was known,
researchers began looking for drugs that would fit into the active site and
block it. If this strategy for stopping HIV infections were successful, it
would be an example of what phenomenon?
A)
vaccination
B)
denaturation
C)
allosteric regulation
D)
competitive inhibition
Use
the following information to answer the questions below.
A
series of enzymes catalyze the reaction X → Y → Z → A. Product A binds to the
enzyme that converts X to Y at a position remote from its active site. This
binding decreases the activity of the enzyme.
53)
What is substance X?
A)
an allosteric inhibitor
B)
a substrate
C)
an intermediate
D)
the product
54)
With respect to the enzyme that converts X to Y, substance A functions as
_____.
A)
an allosteric inhibitor
B)
the substrate
C)
an intermediate
D)
a competitive inhibitor
55)
The mechanism in which the end product of a metabolic pathway inhibits an
earlier step in the pathway is most precisely described as _____.
A)
metabolic inhibition
B)
feedback inhibition
C)
allosteric inhibition
D)
noncooperative inhibition
56)
You have isolated a previously unstudied protein, identified its complete
structure in detail, and determined that it catalyzes the breakdown of a large
substrate. You notice it has two binding sites. One of these is large,
apparently the bonding site for the large substrate; the other is small,
possibly a binding site for a regulatory molecule. What do these findings tell
you about the mechanism of this protein?
A)
It is probably a structural protein that is involved in cell-to-cell adhesion.
B)
It is probably an enzyme that works through allosteric regulation.
C)
It is probably an enzyme that works through competitive inhibition.
D)
It is probably a cell membrane transport protein–like an ion channel.
57)
Allosteric enzyme regulation is usually associated with _____.
A)
feedback inhibition
B)
activating activity
C)
an enzyme with more than one subunit
D)
the need for cofactors
58)
Which of the following is an example of cooperativity?
A)
the binding of an end product of a metabolic pathway to the first enzyme that
acts in the pathway
B)
one enzyme in a metabolic pathway passing its product to act as a substrate for
the next enzyme in the pathway
C)
a molecule binding at one unit of a tetramer, allowing faster binding at each
of the other three
D)
binding of an ATP molecule along with one of the substrate molecules in an
active site
59)
Besides turning enzymes on or off, what other means does a cell use to control
enzymatic activity?
A)
localization of enzymes into specific organelles or membranes
B)
exporting enzymes out of the cell
C)
connecting enzymes into large aggregates
D)
hydrophobic interactions
60)
Protein kinases are enzymes that transfer the terminal phosphate from ATP to an
amino acid residue on the target protein. Many are located on the plasma
membrane as integral membrane proteins or peripheral membrane proteins. What
purpose may be served by their plasma membrane localization?
A)
ATP is more abundant near the plasma membrane.
B)
They can more readily encounter and phosphorylate other membrane proteins.
C)
Membrane localization lowers the activation energy of the phosphorylation
reaction.
D)
They flip back and forth across the membrane to access target proteins on
either side.
61)
Biological systems use free energy based on empirical data that all organisms
require a constant energy input. The first law of thermodynamics states that
energy can be neither created nor destroyed. For living organisms, which of the
following statements is an important consequence of this first law?
A)
The energy content of an organism is constant except for when its cells are
dividing.
B)
The organism must ultimately obtain all the necessary energy for life from its
environment.
C)
The entropy of an organism decreases with time as the organism grows in
complexity.
D)
Organisms are unable to transform energy from the different states in which it
can exist.
62)
In a biological reaction, succinate dehydrogenase catalyzes the conversion of
succinate to fumarate. The reaction is inhibited by malonic acid, a substance
that resembles succinate but cannot be acted upon by succinate dehydrogenase.
Increasing the amount of succinate molecules to those of malonic acid reduces
the inhibitory effect if malonic acid. Select the correct identification of the
molecules described in the reaction.
A)
Succinate dehydrogenase is the enzyme, and fumarate is the substrate in the
reaction.
B)
Succinate dehydrogenase is the enzyme, and malonic acid is the substrate in the
reaction.
C)
Succinate is the substrate, and fumarate is the product in the reaction.
D)
Fumarate is the product, and malonic acid is a noncompetitive inhibitor in the reaction.
Campbell Biology, 10e (Reece)
Chapter 9 Cellular
Respiration and Fermentation
1)
Substrate-level phosphorylation occurs _____.
A)
in glycolysis
B)
in the citric acid cycle
C)
in both glycolysis and the citric acid cycle
D)
during oxidative phosphorylation
2)
The molecule that functions as the reducing agent (electron donor) in a redox
or oxidation-reduction reaction _____.
A)
gains electrons and gains potential energy
B)
loses electrons and loses potential energy
C)
gains electrons and loses potential energy
D)
loses electrons and gains potential energy
3)
When electrons move closer to a more electronegative atom, what happens? The
more electronegative atom is _____.
A)
reduced, and energy is released
B)
reduced, and energy is consumed
C)
oxidized, and energy is consumed
D)
oxidized, and energy is released
4)
Which of the listed statements describes the results of the following reaction?
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
A)
C6H12O6 is oxidized and O2 is reduced.
B)
O2 is oxidized and H2O is reduced.
C)
CO2 is reduced and O2 is oxidized.
D)
O2 is reduced and CO2 is oxidized.
5)
When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction
reaction, the molecule becomes _____.
A)
hydrolyzed
B)
oxidized
C)
reduced
D)
an oxidizing agent
6)
When a molecule of NAD+ (nicotinamide adenine
dinucleotide) gains a hydrogen atom (not a proton), the molecule becomes _____.
A)
dehydrogenated
B)
oxidized
C)
reduced
D)
redoxed
7)
Which of the following statements about NAD+ is true?
A)
NAD+ is reduced to NADH during glycolysis, pyruvate
oxidation, and the citric acid cycle.
B)
NAD+ has more chemical energy than NADH.
C)
NAD+ can donate electrons for use in oxidative
phosphorylation.
D)
In the absence of NAD+, glycolysis can still function.
8)
The oxygen consumed during cellular respiration is involved directly in which
process or event?
A)
glycolysis
B)
accepting electrons at the end of the electron transport chain
C)
the citric acid cycle
D)
the oxidation of pyruvate to acetyl CoA
9)
Carbohydrates and fats are considered high-energy foods because they _____.
A)
have a lot of oxygen atoms.
B)
have no nitrogen in their makeup.
C)
have a lot of electrons associated with hydrogen.
D)
are easily reduced.
10)
A cell has enough available ATP to meet its needs for about 30 seconds. What is
likely to happen when an athlete exhausts his or her ATP supply?
A)
He or she has to sit down and rest.
B)
Catabolic processes are activated that generate more ATP.
C)
ATP is transported into the cell from the circulatory system.
D)
Other cells take over, and the muscle cells that have used up their ATP cease
to function.
11)
Substrate-level phosphorylation accounts for approximately what percentage of
the ATP formed by the reactions of glycolysis?
A)
0%
B)
2%
C)
38%
D)
100%
12)
The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mol and the free energy
for the reduction of NAD+ to NADH is +53 kcal/mol.
Why are only two molecules of NADH formed during glycolysis when it appears
that as many as a dozen could be formed?
A)
Most of the free energy available from the oxidation of glucose is used in the
production of ATP in glycolysis.
B)
Glycolysis is a very inefficient reaction, with much of the energy of glucose
released as heat.
C)
Most of the free energy available from the oxidation of glucose remains in
pyruvate, one of the products of glycolysis.
D)
There is no CO2 or water produced as products of glycolysis.
13)
Starting with one molecule of glucose, the energy-containing products of
glycolysis are _____.
A)
2 NAD+,
2 pyruvate, and 2 ATP
B)
2 NADH, 2 pyruvate, and 2 ATP
C)
2 FADH2,
2 pyruvate, and 4 ATP
D)
6 CO2, 2
pyruvate, and 2 ATP
14)
In glycolysis, for each molecule of glucose oxidized to pyruvate _____.
A)
two molecules of ATP are used and two molecules of ATP are produced.
B)
two molecules of ATP are used and four molecules of ATP are produced.
C)
four molecules of ATP are used and two molecules of ATP are produced.
D)
two molecules of ATP are used and six molecules of ATP are produced.
15)
Which kind of metabolic poison would most directly interfere with glycolysis?
A)
an agent that reacts with oxygen and depletes its concentration in the cell
B)
an agent that binds to pyruvate and inactivates it
C)
an agent that closely mimics the structure of glucose but is not metabolized
D)
an agent that reacts with NADH and oxidizes it to NAD+
16)
Most of the CO2 from the catabolism of glucose is released
during _____.
A)
glycolysis
B)
electron transport
C)
chemiosmosis
D)
the citric acid cycle
17)
Following glycolysis and the citric acid cycle, but before the electron
transport chain and oxidative phosphorylation, the carbon skeleton of glucose
has been broken down to CO2 with some net gain of
ATP. Most of the energy from the original glucose molecule at that point in the
process, however, is in the form of _____.
A)
acetyl-CoA
B)
glucose
C)
pyruvate
D)
NADH
18)
Which electron carrier(s) function in the citric acid cycle?
A)
NAD+ only
B)
NADH and FADH2
C)
the electron transport chain
D)
ADP and ATP
19)
If you were to add one of the eight citric acid cycle intermediates to the
culture medium of yeast growing in the laboratory, what do you think would
happen to the rates of ATP and carbon dioxide production?
A)
There would be no change in ATP production, but we would observe an increased
rate of carbon dioxide production.
B)
The rates of ATP production and carbon dioxide production would both increase.
C)
The rate of ATP production would decrease, but the rate of carbon dioxide
production would increase.
D)
Rates of ATP and carbon dioxide production would probably both decrease.
20)
Carbon dioxide (CO2)
is released during which of the following stages of cellular respiration?
A)
glycolysis and the oxidation of pyruvate to acetyl CoA
B)
oxidation of pyruvate to acetyl CoA and the citric acid cycle
C)
oxidative phosphorylation and fermentation
D)
fermentation and glycolysis
21)
If glucose is the sole energy source, what fraction of the carbon dioxide
exhaled by animals is generated by the reactions of the citric acid cycle?
A) 1/6
B) 1/3
C) 2/3
D) all of it
Use
the following figure to answer the questions below.
The
citric acid cycle.
22)
For each mole of glucose (C6H12O6) oxidized by
cellular respiration, how many moles of CO2 are released in the citric acid cycle (see the
accompanying figure)?
A)
2
B)
4
C)
6
D)
32
23)
If pyruvate oxidation is blocked, what will happen to the levels of
oxaloacetate and citric acid in the citric acid cycle shown in the accompanying
figure?
A)
Oxaloacetate will decrease and citric acid will accumulate.
B)
Oxaloacetate will accumulate and citric acid will decrease.
C)
Both oxaloacetate and citric acid will decrease.
D)
Both oxaloacetate and citric acid will accumulate.
24)
Starting with citrate, which of the following combinations of products would
result from three acetyl CoA molecules entering the citric acid cycle (see the
accompanying figure)?
A)
1 ATP, 2 CO2,
3 NADH, and 1 FADH2
B)
3 ATP, 3 CO2,
3 NADH, and 3 FADH2
C)
3 ATP, 6 CO2,
9 NADH, and 3 FADH2
D)
38 ATP, 6 CO2,
3 NADH, and 12 FADH2
Use
the following information to answer the questions below.
In
the presence of oxygen, the three-carbon compound pyruvate can be catabolized
in the citric acid cycle. First, however, the pyruvate (1) loses a carbon,
which is given off as a molecule of CO2, (2) is oxidized to form a two-carbon
compound called acetate, and (3) is bonded to coenzyme A.
25)
The three listed steps result in the formation of _____.
A)
acetyl CoA, O2,
and ATP
B)
acetyl CoA, FADH2,
and CO2
C)
acetyl CoA, NADH, and CO2
D)
acetyl CoA, NAD+,
ATP, and CO2
26)
Which one of the following is formed by the removal of a carbon (as CO2) from a
molecule of pyruvate?
A)
glyceraldehyde 3-phosphate
B)
oxaloacetate
C)
acetyl CoA
D)
citrate
27)
Which of the following events takes place in the electron transport chain?
A)
the breakdown of glucose into two pyruvate molecules
B)
the breakdown of an acetyl group to carbon dioxide
C)
the extraction of energy from high-energy electrons remaining from glycolysis
and the citric acid cycle
D)
substrate-level phosphorylation
28)
The electron transport chain _____.
A)
is a series of redox reactions
B)
is a series of substitution reactions
C)
is driven by ATP consumption
D)
takes place in the cytoplasm of prokaryotic cells
29)
The chemiosmotic hypothesis is an important concept in our understanding of cellular
metabolism in general because it explains _____.
A)
how ATP is synthesized by a proton motive force
B)
how electron transport can fuel substrate-level phosphorylation
C)
the sequence of the electron transport chain molecules
D)
the reduction of oxygen to water in the final steps of oxidative metabolism
30)
During aerobic respiration, electrons travel downhill in which sequence?
A)
glucose → NADH → electron transport chain → oxygen
B)
glucose → pyruvate → ATP → oxygen
C)
glucose → ATP → electron transport chain → NADH
D)
food → glycolysis → citric acid cycle → NADH → ATP
31)
Where are the proteins of the electron transport chain located?
A)
mitochondrial outer membrane
B)
mitochondrial inner membrane
C)
mitochondrial intermembrane space
D)
mitochondrial matrix
32)
During aerobic respiration, which of the following directly donates electrons
to the electron transport chain at the lowest energy level?
A)
NADH
B)
ATP
C)
ADP + i
i
D)
FADH2
33)
The primary role of oxygen in cellular respiration is to _____.
A)
yield energy in the form of ATP as it is passed down the respiratory chain
B)
act as an acceptor for electrons and hydrogen, forming water
C)
combine with carbon, forming CO2
D)
combine with lactate, forming pyruvate
34)
During aerobic respiration, H2O is formed. Where does the oxygen atom for the
formation of the water come from?
A)
carbon dioxide (CO2)
B)
glucose (C6H12O6)
C)
molecular oxygen (O2)
D)
pyruvate (C3H3O3-)
35)
In chemiosmosis, what is the most direct source of energy that is used to
convert ADP + i to ATP?
i to ATP?
A)
energy released as electrons flow through the electron transport system
B)
energy released from substrate-level phosphorylation
C)
energy released from movement of protons through ATP synthase, down their
electrochemical gradient
D)
No external source of energy is required because the reaction is exergonic.
36)
Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic cells?
A)
mitochondrial outer membrane
B)
mitochondrial inner membrane
C)
mitochondrial intermembrane space
D)
mitochondrial matrix
37)
When hydrogen ions are pumped from the mitochondrial matrix across the inner
membrane and into the intermembrane space, the result is the _____.
A)
formation of ATP
B)
reduction of NAD+
C)
creation of a proton-motive force
D)
lowering of pH in the mitochondrial matrix
38)
Approximately how many molecules of ATP are produced from the complete
oxidation of one molecule of glucose (C6H12O6) in aerobic cellular respiration?
A)
2
B)
4
C)
18-24
D)
30-32
39)
The synthesis of ATP by oxidative phosphorylation, using the energy released by
movement of protons across the membrane down their electrochemical gradient, is
an example of _____.
A)
active transport
B)
an endergonic reaction coupled to an exergonic reaction
C)
a reaction with a positive ΔG
D)
allosteric regulation
40)
If a cell is able to synthesize 30 ATP molecules for each molecule of glucose
completely oxidized to carbon dioxide and water, approximately how many ATP
molecules can the cell synthesize for each molecule of pyruvate oxidized to
carbon dioxide and water?
A)
0
B)
12
C)
14
D)
26
41)
In liver cells, the inner mitochondrial membranes are about five times the area
of the outer mitochondrial membranes. What purpose must this serve?
A)
It allows for an increased rate of glycolysis.
B)
It allows for an increased rate of the citric acid cycle.
C)
It increases the surface for oxidative phosphorylation.
D)
It increases the surface for substrate-level phosphorylation.
42)
You have a friend who lost 7 kg (about 15 pounds) of fat on a regimen of strict
diet and exercise. How did the fat leave his body?
A)
It was released as CO2 and H2O.
B)
It was converted to heat and then released.
C)
It was converted to ATP, which weighs much less than fat.
D)
It was converted to urine and eliminated from the body.
Use
the following information to answer the questions below.
Exposing
inner mitochondrial membranes to ultrasonic vibrations will disrupt the
membranes. However, the fragments will reseal "inside out." The
little vesicles that result can still transfer electrons from NADH to oxygen
and synthesize ATP.
43)
After the disruption, when electron transfer and ATP synthesis still occur,
what must be present?
A)
all of the electron transport proteins and ATP synthase
B)
all of the electron transport system and the ability to add CoA to acetyl
groups
C)
the ATP synthase system
D)
the electron transport system
44)
These inside-out membrane vesicles will _____.
A)
become acidic inside the vesicles when NADH is added
B)
become alkaline inside the vesicles when NADH is added
C)
make ATP from ADP and i if
transferred to a pH 4 buffered solution after incubation in a pH 7 buffered
solution
i if
transferred to a pH 4 buffered solution after incubation in a pH 7 buffered
solution
D)
hydrolyze ATP to pump protons out of the interior of the vesicle to the
exterior
45)
Chemiosmotic ATP synthesis (oxidative phosphorylation) occurs in _____.
A)
all cells, but only in the presence of oxygen
B)
only eukaryotic cells, in the presence of oxygen
C)
only in mitochondria, using either oxygen or other electron acceptors
D)
all respiring cells, both prokaryotic and eukaryotic, using either oxygen or
other electron acceptors
46)
Which of the following normally occurs regardless of whether or not oxygen (O2) is present?
A)
glycolysis
B)
fermentation
C)
citric acid cycle
D)
oxidative phosphorylation (chemiosmosis)
47)
Which of the following occurs in the cytosol of a eukaryotic cell?
A)
glycolysis and fermentation
B)
fermentation and chemiosmosis
C)
oxidation of pyruvate to acetyl CoA
D)
citric acid cycle
48)
In the absence of oxygen, yeast cells can obtain energy by fermentation,
resulting in the production of _____.
A)
ATP, CO2,
and ethanol (ethyl alcohol)
B)
ATP, CO2,
and lactate
C)
ATP, NADH, and pyruvate
D)
ATP, pyruvate, and acetyl CoA
49)
One function of both alcohol fermentation and lactic acid fermentation is to
_____.
A)
reduce NAD+ to NADH
B)
reduce FAD+ to FADH2
C)
oxidize NADH to NAD+
D)
reduce FADH2 to FAD+
50)
An organism is discovered that thrives in both the presence and absence of
oxygen in the air. Curiously, the consumption of sugar increases as oxygen is
removed from the organism's environment, even though the organism does not gain
much weight. This organism _____.
A)
is a normal eukaryotic organism
B)
is photosynthetic
C)
is an anaerobic organism
D)
is a facultative anaerobe
51)
Why is glycolysis considered to be one of the first metabolic pathways to have
evolved?
A)
It produces much less ATP than does oxidative phosphorylation.
B)
It does not involve organelles or specialized structures, does not require
oxygen, and is present in most organisms.
C)
It is found in prokaryotic cells but not in eukaryotic cells.
D)
It requires the presence of membrane-enclosed cell organelles found only in
eukaryotic cells.
52)
Yeast cells that have defective mitochondria incapable of respiration will be
able to grow by catabolizing which of the following carbon sources for energy?
A)
glucose
B)
proteins
C)
fatty acids
D)
Such yeast cells will not be capable of catabolizing any food molecules, and
therefore, will die.
53)
What is the oxidizing agent in the following reaction?
Pyruvate + NADH + H+ → Lactate + NAD+
A) NADH
B) NAD+
C) lactate
D) pyruvate
54)
High levels of citric acid inhibit the enzyme phosphofructokinase, a key enzyme
in glycolysis. Citric acid binds to the enzyme at a different location from the
active site. This is an example of _____.
A)
competitive inhibition
B)
allosteric regulation
C)
the specificity of enzymes for their substrates
D)
positive feedback regulation
55)
Glycolysis is active when cellular energy levels are _____; the regulatory
enzyme, phosphofructokinase, is _____ by ATP.
A)
low; activated
B)
low; inhibited
C)
high; activated
D)
high; inhibited
56)
Canine phosphofructokinase (PFK) deficiency afflicts Springer spaniels,
affecting an estimated 10% of the breed. Given its critical role in glycolysis,
one implication of the genetic defect resulting in PFK deficiency in dogs is
_____.
A)
early embryonic mortality
B)
elevated blood-glucose levels in the dog's blood
C)
an intolerance for exercise
D)
a reduced life span
57)
A young dog has never had much energy. He is brought to a veterinarian for help
and she decides to conduct several diagnostic tests. She discovers that the
dog's mitochondria can use only fatty acids and amino acids for respiration,
and his cells produce more lactate than normal. Of the following, which is the
best explanation of the dog's condition?
A)
His mitochondria lack the transport protein that moves pyruvate across the
outer mitochondrial membrane.
B)
His cells cannot move NADH from glycolysis into the mitochondria.
C)
His cells lack the enzyme in glycolysis that forms pyruvate.
D)
His cells have a defective electron transport chain, so glucose goes to lactate
instead of to acetyl CoA.
58)
Even though plants cells photosynthesize, they still use their mitochondria for
oxidation of pyruvate. This will occur in _____.
A)
photosynthetic cells in the light, while photosynthesis occurs concurrently
B)
cells that are storing glucose only
C)
all cells all the time
D)
photosynthesizing cells in the light and in other tissues in the dark
59)
In respiration, beta oxidation involves the _____.
A)
oxidation of glucose
B)
oxidation of pyruvate
C)
regulation of glycolysis
D)
breakdown of fatty acids
60)
Fatty acids usually have an even number of carbons in their structures. They
are catabolized by a process called beta-oxidation. The end products of the
metabolic pathway are acetyl groups of acetyl CoA molecules. These acetyl
groups _____.
A)
directly enter the electron transport chain
B)
directly enter the energy-yielding stages of glycolysis
C)
are directly decarboxylated by pyruvate dehydrogenase
D)
directly enter the citric acid cycle
61)
New biosensors, applied like a temporary tattoo to the skin, can alert serious
athletes that they are about to "hit the wall" and find it difficult
to continue exercising. These biosensors monitor lactate, a form of lactic
acid, released in sweat during strenuous exercise.
Which
of the statements below is the best explanation of why athletes would need to
monitor lactate levels?
A)
During aerobic respiration, muscle cells cannot produce enough lactate to fuel
muscle cell contractions and muscles begin to cramp, thus athletic performance
suffers.
B)
During anaerobic respiration, lactate levels increase when muscles cells need
more energy, however muscles cells eventually fatigue, thus athletes should
modify their activities to increase aerobic respiration.
C)
During aerobic respiration, muscles cells produce too much lactate which causes
a rise in the pH of the muscle cells, thus athletes must consume increased
amounts of sports drinks, high in electrolytes, to buffer the pH.
D)
During anaerobic respiration, muscle cells receive too little oxygen and begin
to convert lactate to pyruvate (pyruvic acid), thus athletes experience
cramping and fatigue.
Campbell Biology, 10e (Reece)
Chapter 10
Photosynthesis
1)
The process of photosynthesis probably originated _____.
A)
in plants
B)
in prokaryotes
C)
in fungi
D)
three separate times during evolution
2)
In autotrophic bacteria, where is chlorophyll located?
A)
in chloroplast membranes
B)
in the ribosomes
C)
in the nucleoid
D)
in the infolded plasma membrane
3)
Plants photosynthesize _____.
A)
only in the light but respire only in the dark
B)
only in the dark but respire only in the light
C)
only in the light but respire in light and dark
D)
and respire only in the light
4)
Early investigators thought the oxygen produced by photosynthetic plants came
from carbon dioxide. In fact, it comes from _____.
A)
water
B)
glucose
C)
air
D)
electrons from NADPH
5)
If photosynthesizing green algae are provided with CO2 containing heavy oxygen (18O), later
analysis will show that all of the following molecules produced by the algae
contain 18O
EXCEPT _____.
A)
glyceraldehyde 3-phosphate (G3P)
B)
glucose
C)
ribulose bisphosphate (RuBP)
D)
O2
6)
Every ecosystem must have _____.
A)
autotrophs and heterotrophs
B)
producers and primary consumers
C)
photosynthesizers
D)
autotrophs
7)
When oxygen is released as a result of photosynthesis, it is a direct by-product
of _____.
A)
splitting water molecules
B)
chemiosmosis
C)
the electron transfer system of photosystem I
D)
the electron transfer system of photosystem II
8)
Which of the following statements is a correct distinction between autotrophs
and heterotrophs?
A)
Cellular respiration is unique to heterotrophs.
B)
Only heterotrophs have mitochondria.
C)
Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.
D)
Only heterotrophs require oxygen.
Use
the following figure to answer the questions below.
9)
The figure shows the absorption spectrum for chlorophyll a and the
action spectrum for photosynthesis. Why are they different?
A)
Green and yellow wavelengths inhibit the absorption of red and blue
wavelengths.
B)
Oxygen given off during photosynthesis interferes with the absorption of light.
C)
Other pigments absorb light in addition to chlorophyll a.
D)
Aerobic bacteria take up oxygen, which changes the measurement of the rate of
photosynthesis.
10)
What wavelength of light in the figure is most effective in driving
photosynthesis?
A)
420 mm
B)
575 mm
C)
625 mm
D)
730 mm
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.
11)
What did Engelmann conclude about the congregation of bacteria in the red and
blue areas?
A)
Bacteria congregated in these areas due to an increase in the temperature of
the red and blue light.
B)
Bacteria congregated in these areas because these areas had the most oxygen
being released.
C)
Bacteria are attracted to red and blue light and thus these wavelengths are
more reactive than other wavelengths.
D)
Bacteria congregated in these areas due to an increase in the temperature
caused by an increase in photosynthesis.
12)
An outcome of Engelmann's experiment was to help determine the relationship
between _____.
A)
wavelengths of light and the rate of aerobic respiration
B)
wavelengths of light and the amount of heat released
C)
wavelengths of light and the rate of photosynthesis
D)
the concentration of carbon dioxide and the rate of photosynthesis
Use
the following information to answer the questions below.
A
spaceship is designed to support animal life for a multiyear voyage to the
outer planets of the solar system. Plants will be grown to provide oxygen and
to recycle carbon dioxide. Since the spaceship will be too far from the sun for
photosynthesis, an artificial light source will be needed.
13)
What wavelengths of light should be used to maximize plant growth with a
minimum of energy expenditure?
A)
full-spectrum white light
B)
green light
C)
a mixture of blue and red light
D)
UV light
14)
Suppose a plant has a unique photosynthetic pigment and the leaves of this
plant appear to be reddish yellow. What wavelengths of visible light are
absorbed by this pigment?
A)
red and yellow
B)
blue and violet
C)
green and yellow
D)
blue, green, and red
15)
Halobacterium has a photosynthetic membrane that appears purple. Its
photosynthetic action spectrum is the inverse of the action spectrum for green
plants. (That is, the Halobacterium action spectrum has a peak where the
green plant action spectrum has a trough.) What wavelengths of light do the Halobacterium
photosynthetic pigments absorb?
A)
red and yellow
B)
blue, green, and red
C)
green and yellow
D)
blue and red
16)
Why are there several structurally different pigments in the reaction centers
of photosystems?
A)
Excited electrons must pass through several pigments before they can be
transferred to electron acceptors of the electron transport chain.
B)
This arrangement enables the plant to absorb light energy of a variety of
wavelengths.
C)
They enable the plant to absorb more photons from light energy, all of which
are at the same wavelength.
D)
They enable the reaction center to excite electrons to a higher energy level.
17)
If pigments from a particular species of plant are extracted and subjected to
paper chromatography, which of the following is most likely?
A)
Paper chromatography for the plant would isolate a single band of pigment that
is characteristic of that particular plant.
B)
Paper chromatography would separate the pigments from a particular plant into
several bands.
C)
The isolated pigments would be some shade of green.
D)
Paper chromatography would isolate only the pigments that reflect green light.
18)
In autumn, the leaves of deciduous trees change colors. This is because
chlorophyll is degraded and _____.
A)
carotenoids and other pigments are still present in the leaves
B)
the degraded chlorophyll changes into many other colors
C)
water supply to the leaves has been reduced
D)
sugars are sent to most of the cells of the leaves
19)
What event accompanies energy absorption by chlorophyll (or other pigment
molecules of the antenna complex)?
A)
ATP is synthesized from the energy absorbed.
B)
A carboxylation reaction of the Calvin cycle occurs.
C)
Electrons are stripped from NADPH.
D)
An electron is excited.
20)
As electrons are passed through the system of electron carriers associated with
photosystem II, they lose energy. What happens to this energy?
A)
It excites electrons of the reaction center of photosystem I.
B)
It is lost as heat.
C)
It is used to establish and maintain a proton gradient.
D)
It is used to phosphorylate NAD+ to NADPH,
the molecule that accepts electrons from photosystem I.
21)
The final electron acceptor associated with photosystem I is _____.
A)
oxygen
B)
water
C)
NADP
D)
NADPH
22)
The electrons of photosystem II are excited and transferred to electron
carriers. From which molecule or structure do the photosystem II replacement
electrons come?
A)
the electron carrier, plastocyanin
B)
photosystem I
C)
water
D)
oxygen
23)
In the thylakoid membranes, the pigment molecules in a light-harvesting complex
_____.
A)
split water and release oxygen from the reaction-center chlorophyll
B)
absorb and transfer light energy to the reaction-center chlorophyll
C)
synthesize ATP from ADP and i
i
D)
transfer electrons to ferredoxin and then NADPH
24)
Which of the following are directly associated with photosystem I?
A)
receiving electrons from the thylakoid membrane electron transport chain
B)
generation of molecular oxygen
C)
extraction of hydrogen electrons from the splitting of water
D)
passing electrons to the cytochrome complex
25)
Some photosynthetic organisms contain chloroplasts that lack photosystem II,
yet are able to survive. The best way to detect the lack of photosystem II in
these organisms would be to _____.
A)
determine if they have thylakoids in the chloroplasts
B)
test for liberation of O2 in the light
C)
test for CO2 fixation in the dark
D)
do experiments to generate an action spectrum
26)
What are the products of linear electron flow?
A)
heat and fluorescence
B)
ATP and P700
C)
ATP and NADPH
D)
ADP and NADP+
27)
As a research scientist, you measure the amount of ATP and NADPH consumed by
the Calvin cycle in 1 hour. You find that 30,000 molecules of ATP were
consumed, but only 20,000 molecules of NADPH were consumed. Where did the extra
ATP molecules come from?
A)
photosystem II
B)
photosystem I
C)
cyclic electron flow
D)
linear electron flow
28)
Assume a thylakoid is somehow punctured so that the interior of the thylakoid
is no longer separated from the stroma. This damage will most directly affect
the _____.
A)
splitting of water
B)
flow of electrons from photosystem II to photosystem I
C)
synthesis of ATP
D)
reduction of NADP+
29)
In a plant cell, where are the ATP synthase complexes located?
A)
thylakoid membrane only
B)
inner mitochondrial membrane only
C)
thylakoid membrane and inner mitochondrial membrane
D)
thylakoid membrane and plasma membrane
30)
In mitochondria, chemiosmosis moves protons from the matrix into the intermembrane
space, whereas in chloroplasts, chemiosmosis moves protons from the _____.
A)
matrix to the stroma
B)
stroma to the thylakoid space
C)
intermembrane space to the matrix
D)
thylakoid space to the stroma
31)
Which of the following statements best describes the relationship between
photosynthesis and respiration?
A)
Respiration runs the biochemical pathways of photosynthesis in reverse.
B)
Photosynthesis stores energy in complex organic molecules; respiration releases
energy from complex organic molecules
C)
Photosynthesis occurs only in plants; respiration occurs only in animals.
D)
Photosynthesis is catabolic; respiration is anabolic.
32)
In photosynthetic cells, synthesis of ATP by the chemiosmotic mechanism occurs
during _____.
A)
photosynthesis only
B)
respiration only
C)
photosynthesis and respiration
D)
neither photosynthesis nor respiration
33)
Carbon dioxide is split to form oxygen gas and carbon compounds _____.
A)
during photosynthesis
B)
during respiration
C)
during photosynthesis and respiration
D)
in neither photosynthesis nor respiration
34)
What is the relationship between the wavelength of light and the quantity of
energy per photon?
A)
They have a direct, linear relationship.
B)
They are inversely related.
C)
They are logarithmically related.
D)
They are separate phenomena.
35)
P680+ is said to be the strongest biological
oxidizing agent. Given its function, why is this necessary?
A)
It is the receptor for the most excited electron in either photosystem of
photosynthesis.
B)
It is the molecule that transfers electrons to plastoquinone (Pq) of the
electron transfer system.
C)
It transfers its electrons to reduce NADP+ to NADPH.
D)
It obtains electrons from the oxygen atom in a water molecule, so it must have
a stronger attraction for electrons than oxygen has.
36)
Carotenoids are often found in foods that are considered to have antioxidant
properties in human nutrition. What related function do they have in plants?
A)
They serve as accessory pigments to increase light absorption.
B)
They protect against oxidative damage from excessive light energy.
C)
They shield the sensitive chromosomes of the plant from harmful ultraviolet
radiation.
D)
They reflect orange light and enhance red light absorption by chlorophyll.
37)
In a plant, the reactions that produce molecular oxygen (O2) take place
in _____.
A)
the light reactions alone
B)
the Calvin cycle alone
C)
the light reactions and the Calvin cycle
D)
neither the light reactions nor the Calvin cycle
38)
The accumulation of free oxygen in Earth's atmosphere began with the origin of
_____.
A)
life and respiratory metabolism
B)
cyanobacteria using photosystem II
C)
chloroplasts in photosynthetic eukaryotic algae
D)
land plants
39)
In its mechanism, photophosphorylation is most similar to _____.
A)
substrate-level phosphorylation in glycolysis
B)
oxidative phosphorylation in cellular respiration
C)
the Calvin cycle
D)
reduction of NADP+
40)
Which process is most directly driven by light energy?
A)
creation of a pH gradient by pumping protons across the thylakoid membrane
B)
carbon fixation in the stroma
C)
reduction of NADP+ molecules
D)
removal of electrons from chlorophyll molecules
41)
A gardener is concerned that her greenhouse is getting too hot from too much
light and seeks to shade her plants with colored translucent plastic sheets,
the color of which allows passage of only that wavelength. What color should
she use to reduce overall light energy but still maximize plant growth?
A)
green
B)
blue
C)
orange
D)
Any color will work equally well.
42)
A flask containing photosynthetic green algae and a control flask containing
water with no algae are both placed under a bank of lights, which are set to
cycle between 12 hours of light and 12 hours of dark. The dissolved oxygen
concentrations in both flasks are monitored. Predict what the relative
dissolved oxygen concentrations will be in the flask with algae compared to the
control flask. The dissolved oxygen in the flask with algae will _____.
A)
always be higher
B)
always be lower
C)
be higher in the light, but the same in the dark
D)
be higher in the light, but lower in the dark
43)
Which of the following are products of the light reactions of photosynthesis
that are utilized in the Calvin cycle?
A)
CO2 and glucose
B)
H2O and
O2
C)
ADP, i, and NADP+
i, and NADP+
D)
ATP and NADPH
44)
Where does the Calvin cycle take place?
A)
stroma of the chloroplast
B)
thylakoid membrane
C)
interior of the thylakoid (thylakoid space)
D)
outer membrane of the chloroplast
45)
What is the primary function of the Calvin cycle?
A)
use NADPH to release carbon dioxide
B)
split water and release oxygen
C)
transport RuBP out of the chloroplast
D)
synthesize simple sugars from carbon dioxide
46)
In the process of carbon fixation, RuBP attaches a CO2 to produce a six-carbon molecule, which is
then split to produce two molecules of 3-phosphoglycerate. After
phosphorylation and reduction produces glyceraldehyde 3-phosphate (G3P), what
more needs to happen to complete the Calvin cycle?
A)
addition of a pair of electrons from NADPH
B)
regeneration of ATP from ADP
C)
regeneration of RuBP
D)
regeneration of NADP+
Use
the accompanying figure and the molecules labeled A, B, C, D, and E to answer
the following questions.
47)
Refer to the figure. If the carbon atom of each of the incoming CO2 molecules is labeled with a radioactive
isotope of carbon, which organic molecules will be radioactively labeled after
one cycle?
A)
C only
B)
B, C, D, and E
C)
C, D, and E only
D)
B and C only
48)
Refer to the figure. 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?
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.
49)
Which of the following sequences correctly represents the flow of electrons
during photosynthesis?
A)
NADPH → O2 → C O2
B)
H2O →
NADPH → Calvin cycle
C)
NADPH → chlorophyll → Calvin cycle
D)
NADPH → electron transport chain → O2
50)
Which of the following does NOT occur during the Calvin cycle?
A)
oxidation of NADPH
B)
release of oxygen
C)
regeneration of the CO2 acceptor
D)
consumption of ATP
51)
What compound provides the reducing power for Calvin cycle reactions?
A) ATP
B)
NADH
C)
NADP+
D)
NADPH
52)
What would be the expected effect on plants if the atmospheric CO2 concentration was doubled?
A)
All plants would experience increased rates of photosynthesis.
B)
C3 plants would have faster growth; C4 plants would be minimally affected.
C)
C4 plants would have faster growth; C3 plants would be minimally affected.
D)
C3 plants would have faster growth; C4 plants would have slower growth.
53)
Why are C4 plants able to photosynthesize with no
apparent photorespiration?
A)
They do not participate in the Calvin cycle.
B)
They use PEP carboxylase to initially fix CO2.
C)
They conserve water more efficiently.
D)
They exclude oxygen from their tissues.
54)
CAM plants keep stomata closed in the daytime, thus reducing loss of water. They
can do this because they _____.
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 photosystem I and photosystem II at night
55)
The alternative pathways of photosynthesis using the C4 or CAM systems are said to be compromises.
Why?
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.
56)
If plant gene alterations cause plants to be deficient in photorespiration,
what would most probably occur?
A)
Photosynthetic efficiency would be reduced at low light intensities.
B)
Cells would carry on the Calvin cycle at a much slower rate.
C)
There would be more light-induced damage to the cells.
D)
Less oxygen would be produced.
57)
Compared to C3 plants, C4 plants _____.
A)
can continue to fix CO2 even at lower CO2 concentrations and higher oxygen
concentrations
B)
have higher rates of photorespiration
C)
do not use rubisco for carbon fixation
D)
make a four-carbon compound, oxaloacetate, which is then delivered to the
citric acid cycle in mitochondria
Use
the following figure to answer the questions below.
58)
Which of the following statements is true concerning the accompanying figure?
A)
It represents a C4 photosynthetic system.
B)
It represents an adaptation that maximizes photorespiration.
C)
It represents a C3 photosynthetic system.
D)
It represents a CAM photosynthetic system.
59)
Referring to the accompanying figure, oxygen would inhibit the CO2 fixation reactions in _____.
A)
cell I only
B)
cell II only
C)
neither cell I nor cell II
D)
both cell I and cell II
60)
Photorespiration _____.
A)
generates carbon dioxide and consumes ATP and oxygen
B)
generates ATP and sugars and consumes oxygen and carbon dioxide
C)
generates oxygen and consumes ATP, carbon dioxide, and sugars
D)
consumes carbon dioxide and generates ATP, sugars, and oxygen
61)
Students conducted an experiment to determine the effect of light intensity on
the rate of photosynthesis. They punched 40 leaf disks from spinach leaves and
used a syringe partially filled with water to pull the gases from the leaf
disks so that all leaf disks sunk to the bottom of the syringe. Ten (10) leaf
disks from the syringe were placed in each of four cups and covered with 50 ml
of the solutions as indicated below. All leaf disks were resting on the bottom
of the cups when the experiment began. The volume of liquid in each cup and the
temperature of the solutions were held constant. All cups were placed 0.5
meters from the designated light source. A large beaker of water was placed
between the light and the cups to act as a heat sink to prevent a change in
temperature. At the end of 10 minutes, the number of disks floating in each cup
was recorded.
|
Trial
|
Grams of
baking soda (CO22 source)
|
Wattage of
light bulb
|
Disks floating
at 10 minutes
|
|
1
|
0.5
|
25
|
3
|
|
2
|
0.5
|
50
|
5
|
|
3
|
0.5
|
75
|
9
|
|
4
|
0
|
75
|
0
|
Use
your knowledge of the mechanism of photosynthesis and the data presented in the
chart to determine which of the statements below is a correct explanation for
the student's data.
A)
Cup 1 had a low rate of photosynthesis because 0.5 grams of baking soda did not
provide a sufficient amount of CO2.
B)
Cup 2 had the highest rate of photosynthesis because 5 disks were floating at
the end of 10 minutes using a 50 watt light bulb.
C)
Cup 3 had the same rate of photosynthesis as Cup 1 because they had the same
ratio of disks floating to wattage of light.
D)
Cup 4 had the slowest rate of photosynthesis because it had the least baking
soda.
Campbell Biology, 10e (Reece)
Chapter 11 Cell
Communication
1)
In yeast signal transduction, a yeast cell releases a mating factor which
_____.
A)
acts back on the same cell that secreted the mating factor, changing its
development
B)
passes through the membranes of neighboring cells, binds to DNA, and initiates
transcription
C)
binds to receptors on the membranes of other types of yeast cells
D)
diffuses through the membranes of distant cells, causing them to produce
factors that initiate long-distance migrations
2)
Which of the following statements about quorum sensing is FALSE? Quorum sensing
_____.
A)
is cell-cell communication in eukaryotes
B)
is species specific
C)
may result in biofilm formation
D)
is particularly well studied because of its medical importance
3)
In the formation of biofilms, such as those forming on unbrushed teeth, cell
signaling serves which function?
A)
formation of mating complexes
B)
aggregation of bacteria that can cause cavities
C)
secretion of substances that inhibit foreign bacteria
D)
digestion of unwanted parasite populations
4)
Which of the following is a type of local signaling in which a cell secretes a
signal molecule that affects neighboring cells?
A)
hormonal signaling
B)
autocrine signaling
C)
paracrine signaling
D)
synaptic signaling
5)
Hormones are chemical substances produced in one organ that are released into
the bloodstream and affect the function of a target organ. For the target organ
to respond to a particular hormone, it must _____.
A)
modify its plasma membrane to alter the hormone entering the cytoplasm
B)
be from the same cell type as the organ that produced the hormone
C)
experience an imbalance that disrupts its normal function
D)
have receptors that recognize and bind the hormone molecule
6)
In which of the following ways do plant hormones differ from hormones in
animals?
A)
Plant hormones most often travel in air as a gas.
B)
Animal hormones are only local regulators.
C)
Plant hormones are typically released into the soil.
D)
Animal hormones are primarily for mating and embryonic development.
7)
When a neuron responds to a particular neurotransmitter by opening gated ion
channels, the neurotransmitter is serving as which part of the signal pathway?
A)
relay molecule
B)
transducer
C)
signal molecule
D)
response molecule
The
following questions are based on the accompanying figure.
8)
Which of the following types of signaling is represented in the figure?
A)
autocrine
B)
paracrine
C)
hormonal
D)
synaptic
9)
In the figure, the dots in the space between the two structures represent which
of the following?
A)
receptor molecules
B)
signal transducers
C)
neurotransmitters
D)
hormones
10)
Which observation suggested to Sutherland the involvement of a second messenger
in epinephrine's effect on liver cells?
A)
Receptor studies indicated that epinephrine was a ligand.
B)
Glycogen breakdown was observed only when epinephrine was administered to
intact cells.
C)
Glycogen breakdown was observed when epinephrine and glycogen phosphorylase
were combined.
D)
Epinephrine was known to have different effects on different types of cells.
11)
A G-protein receptor with GTP bound to it _____.
A)
is in its active state
B)
signals a protein to maintain its shape and conformation
C)
will use cGMP as a second messenger
D)
directly affects gene expression
12)
Testosterone functions inside a cell by _____.
A)
acting as a signal receptor that activates tyrosine kinases
B)
binding with a receptor protein that enters the nucleus and activates specific
genes
C)
acting as a steroid signal receptor that activates ion channel proteins
D)
coordinating a phosphorylation cascade that increases spermatogenesis
13)
Scientists have found that extracellular matrix components may induce specific
gene expression in embryonic tissues such as the liver and testes. For this to
happen there must be direct communication between the extracellular matrix and
the developing cells. Which kind of transmembrane protein would most likely be
involved in this kind of induction?
A)
integrins
B)
collagens
C)
actins
D)
fibronectins
14)
One of the major categories of receptors in the plasma membrane reacts by
forming dimers, adding phosphate groups, and then activating relay proteins.
Which type does this?
A)
G protein-coupled receptors
B)
ligand-gated ion channels
C)
steroid receptors
D)
receptor tyrosine kinases
15)
A drug designed to inhibit the response of cells to testosterone would most
likely result in _____.
A)
lower cytoplasmic levels of cAMP
B)
a decrease in transcriptional activity of certain genes
C)
an increase in cytosolic calcium concentration
D)
a decrease in G protein activity
Use
this description to answer the following questions.
A
major group of G protein-coupled receptors contains seven transmembrane α
helices. The amino end of the protein lies at the exterior of the plasma
membrane. Loops of amino acids connect the helices either at the exterior face
or on the cytosol face of the membrane. The loop on the cytosol side between
helices 5 and 6 is usually substantially longer than the others.
16)
Where would you expect to find the carboxyl end?
A)
at the exterior surface
B)
at the cytosol surface
C)
connected with the loop at H5 and H6
D)
between the membrane layers
17)
The coupled G protein most likely interacts with this receptor _____.
A)
at the NH3 end
B)
at the COO– end
C)
along the exterior margin
D)
at the loop between H5 and H6
18)
Binding of a signaling molecule to which type of receptor leads directly to a
change in the distribution of ions on opposite sides of the membrane?
A)
receptor tyrosine kinase
B)
G protein-coupled receptor
C)
ligand-gated ion channel
D)
intracellular receptor
19)
Lipid-soluble signaling molecules, such as testosterone, cross the membranes of
all cells but affect only target cells because _____.
A)
only target cells retain the appropriate DNA segments
B)
intracellular receptors are present only in target cells
C)
only target cells possess the cytosolic enzymes that transduce the testosterone
D)
only in target cells is testosterone able to initiate the phosphorylation
cascade leading to activated transcription factor
20)
If an animal cell suddenly lost the ability to produce GTP, what might happen
to its signaling system?
A)
It would not be able to activate and inactivate the G protein on the
cytoplasmic side of the plasma membrane.
B)
It would be able to carry out reception and transduction but would not be able
to respond to a signal.
C)
It would use ATP instead of GTP to activate and inactivate the G protein on the
cytoplasmic side of the plasma membrane.
D)
It would employ a transduction pathway directly from an external messenger.
21)
Which of the following is true of steroid receptors?
A)
The receptor molecules are themselves lipids or glycolipids.
B)
The receptor may be inside the nucleus of a target cell.
C)
The unbound steroid receptors are quickly recycled by lysosomes.
D)
Steroid receptors are typically bound to the external surface of the nuclear
membrane.
22)
Particular receptor tyrosine kinases (RTKs) that promote excessive cell
division are found at high levels on various cancer cells. A protein,
Herceptin, has been found to bind to an RTK known as HER2. HER2 is sometimes
excessive in cancer cells. This information can now be utilized in breast
cancer treatment if which of the following is true?
A)
if HER2, administered by injection, causes cell division
B)
if the patient's cancer cells have excessive levels of HER2
C)
if the patient's genome codes for the HER2 receptor
D)
if the patient has RTKs only in cancer cells
23)
Which of the following would be inhibited by a drug that specifically blocks
the addition of phosphate groups to proteins?
A)
G protein-coupled receptor binding
B)
ligand-gated ion channel signaling
C)
adenylyl cyclase activity
D)
receptor tyrosine kinase activity
24)
Which of the following is characteristic of a steroid hormone action?
A)
protein phosphorylation
B)
cell-surface receptor binding
C)
internal receptor binding
D)
second messenger activation
25)
The receptors for steroid hormones are located inside the cell instead of on
the membrane surface like most other signal receptors. This is not a problem
for steroids because _____.
A)
the receptors can be readily stimulated to exit and relocate on the membrane surface
B)
steroids do not directly affect cells but instead alter the chemistry of blood
plasma
C)
steroid hormones are lipid soluble, so they can readily diffuse through the
lipid bilayer of the cell membrane
D)
steroids must first bond to a steroid activator, forming a complex that then
binds to the cell surface
26)
Not all intercellular signals require transduction. Which one of the following
signals would be processed without transduction?
A)
a lipid-soluble signal
B)
a signal that is weakly bound to a nucleotide
C)
a signal that binds to a receptor in the cell membrane
D)
a signal that binds to the ECM
27)
What does it mean to say that a signal is transduced?
A)
The signal enters the cell directly and binds to a receptor inside.
B)
The physical form of the signal changes from one form to another.
C)
The signal is amplified, such than even a single molecule evokes a large
response.
D)
The signal triggers a sequence of phosphorylation events inside the cell.
28)
Protein phosphorylation is commonly involved with all of the following EXCEPT
_____.
A)
regulation of transcription by extracellular signaling molecules
B)
enzyme activation
C)
activation of G protein-coupled receptors
D)
activation of protein kinase molecules
29)
In general, a signal transmitted via phosphorylation of a series of proteins
_____.
A)
results in a conformational change to each protein
B)
requires binding of a hormone to an intracellular receptor
C)
activates a transcription event
D)
generates ATP in the process of signal transduction
30)
Which of the following is the best explanation for the inability of a specific
animal cell to reduce the Ca2+ concentration in its cytosol compared with the
extracellular fluid?
A)
blockage of the synaptic signal
B)
loss of transcription factors
C)
insufficient ATP levels in the cytosol
D)
low levels of protein kinase in the cell
31)
The toxin of Vibrio cholerae causes profuse diarrhea because it _____.
A)
modifies a G protein involved in regulating salt and water secretion
B)
binds with adenylyl cyclase and triggers the formation of cAMP
C)
signals IP3 to act as a second messenger for the release
of calcium
D)
modifies calmodulin and activates a cascade of protein kinases
32)
Which of the following would most likely be an immediate result of a growth
factor binding to its receptor?
A)
protein kinase activity
B)
adenylyl cyclase activity
C)
protein phosphatase activity
D)
phosphorylase activity
33)
Adenylyl cyclase has the opposite effect of which of the following?
A)
protein kinase
B)
protein phosphatase
C)
phosphodiesterase
D)
phosphorylase
34)
Caffeine is an inhibitor of phosphodiesterase. Therefore, the cells of a person
who has recently consumed coffee would have increased levels of _____.
A)
phosphorylated proteins
B)
cAMP
C)
adenylyl cyclase
D)
activated G proteins
35)
An inhibitor of which of the following could be used to block the release of
calcium from the endoplasmic reticulum?
A)
serine/threonine kinases
B)
phosphodiesterase
C)
phospholipase C
D)
adenylyl cyclase
36)
Which of the following statements is true of signal molecules?
A)
When signal molecules first bind to receptor tyrosine kinases, the receptors
phosphorylate a number of nearby molecules.
B)
In response to some G protein-mediated signals, a special type of lipid
molecule associated with the plasma membrane is cleaved to form IP3 and calcium.
C)
In most cases, signal molecules interact with the cell at the plasma membrane,
enter the cell, and eventually enter the nucleus.
D)
Protein kinase A activation is one possible result of signal molecules binding
to G protein-coupled receptors.
37)
Which of the following is a correct association?
A)
kinase activity and the addition of a tyrosine
B)
phosphodiesterase activity and the removal of phosphate groups
C)
GTPase activity and hydrolysis of GTP to GDP
D)
adenylyl cyclase activity and the conversion of cAMP to AMP
38)
Protein kinase is an enzyme that _____.
A)
functions as a second messenger molecule
B)
serves as a receptor for various signal molecules
C)
activates or inactivates other proteins by adding a phosphate group to them
D)
produces second messenger molecules
39)
Viagra causes dilation of blood vessels and increased blood flow to the penis,
facilitating erection. Viagra acts by inhibiting _____.
A)
the hydrolysis of cGMP to GMP
B)
the hydrolysis of GTP to GDP
C)
the dephosphorylation of cGMP
D)
the removal of GMP from the cell
40)
Which of the following amino acids are most frequently phosphorylated by
protein kinases in the cytoplasm during signal transduction?
A)
tyrosines
B)
glycine and histidine
C)
serine and threonine
D)
glycine and glutamic acid
41)
In signal transduction, phosphatases _____.
A)
move the phosphate group of the transduction pathway to the next molecule of a
series
B)
prevent a protein kinase from being reused when there is another extracellular
signal
C)
amplify the second messengers such as cAMP
D)
inactivate protein kinases and turn off the signal transduction
42)
If a pharmaceutical company wished to design a drug to maintain low blood sugar
levels, one approach might be to design a compound _____.
A)
that activates epinephrine receptors
B)
that increases cAMP production in liver cells
C)
to block G protein activity in liver cells
D)
that increases phosphorylase activity
43)
If a pharmaceutical company wished to design a drug to maintain low blood sugar
levels, one approach might be to design a compound _____.
A)
that mimics epinephrine and can bind to the epinephrine receptor
B)
that stimulates cAMP production in liver cells
C)
to stimulate G protein activity in liver cells
D)
that increases phosphodiesterase activity
44)
Consider this pathway: epinephrine → G protein-coupled receptor → G protein →
adenylyl cyclase → cAMP. The second messenger in this pathway is _____.
A)
cAMP
B)
G protein
C)
adenylyl cyclase
D)
G protein-coupled receptor
45)
Sutherland discovered that the signaling molecule epinephrine _____.
A)
brings about a decrease in levels of cAMP as a result of bypassing the plasma
membrane
B)
causes lower blood glucose by binding to liver cells
C)
interacts directly with glycogen phosphorylase
D)
elevates cytosolic concentrations of cyclic AMP
46)
Which of the following is true during a typical cAMP-type signal transduction
event?
A)
The second messenger is the last part of the system to be activated.
B)
The hormone activates the second messenger by directly binding to it.
C)
The second messenger amplifies the hormonal response by attracting more
hormones to the cell being affected.
D)
Adenylyl cyclase is activated after the hormone binds to the cell and before
phosphorylation of proteins occurs.
47)
Put the steps of the process of signal transduction in the order they occur:
1. A
conformational change in the signal-receptor complex activates an enzyme.
2. Protein
kinases are activated.
3. A
signal molecule binds to a receptor.
4. Target
proteins are phosphorylated.
5. Second
messenger molecules are released.
A)
1, 2, 3, 4, 5
B)
3, 1, 2, 4, 5
C)
3, 1, 5, 2, 4
D)
1, 2, 5, 3, 4
48)
Transcription factors _____.
A)
regulate the synthesis of DNA in response to a signal
B)
transcribe ATP into cAMP
C)
control gene expression
D)
regulate the synthesis of lipids in the cytoplasm
49)
At puberty, an adolescent female body changes in both structure and function of
several organ systems, primarily under the influence of changing concentrations
of estrogens and other steroid hormones. How can one hormone, such as estrogen,
mediate so many effects?
A)
Estrogen is produced in very large concentration by nearly every tissue of the
body.
B)
Each cell responds in the same way when steroids bind to the cell surface.
C)
Estrogen is kept away from the surface of any cells not able to bind it at the
surface.
D)
Estrogen binds to specific receptors inside many kinds of cells, each with
different responses.
50)
Scaffolding proteins are _____.
A)
microtubular protein arrays that allow lipid-soluble hormones to get from the
cell membrane to the nuclear pores
B)
large molecules to which several relay proteins attach to facilitate cascade
effects
C)
relay proteins that orient receptors and their ligands in appropriate
directions to facilitate their complexing
D)
proteins that can reach into the nucleus of a cell to affect transcription
51)
Phosphorylation cascades involving a series of protein kinases are useful for
cellular signal transduction because they _____.
A)
are species specific
B)
always lead to the same cellular response
C)
amplify the original signal many times
D)
counter the harmful effects of phosphatases
52)
GTPase activity is important in the regulation of signal transduction because
it _____.
A)
increases the available concentration of phosphate
B)
decreases the amount of G protein in the membrane
C)
hydrolyzes GTP to GDP, thus shutting down the pathway
D)
converts cGMP to GTP
53)
Why has C. elegans proven to be a useful model for understanding
apoptosis?
A)
The animal does not naturally use apoptosis, but can be induced to do so in the
laboratory.
B)
The nematode undergoes a fixed and easy-to-visualize number of apoptotic events
during its normal development.
C)
This plant has a long-studied aging mechanism that has made understanding its
death just a last stage.
D)
While the organism ages, its cells die progressively until the whole organism
is dead.
54)
Which of the following describes the events of apoptosis?
A)
The cell dies, it is lysed, its organelles are phagocytized, and its contents
are recycled.
B)
The cell's DNA and organelles become fragmented, the cell dies, and it is
phagocytized.
C)
The cell's DNA and organelles become fragmented, the cell shrinks and forms
blebs, and the cell's parts are packaged in vesicles that are digested by
specialized cells.
D)
The cell's nucleus and organelles are lysed, then the cell enlarges and bursts.
55)
If an adult person has a faulty version of the human analog to ced-4 of
the nematode, which of the following is most likely to result?
A)
activation of a developmental pathway found in the worm but not in humans
B)
a form of cancer in which there is insufficient apoptosis
C)
formation of molecular pores in the mitochondrial outer membrane
D)
excess skin loss
56)
Why is apoptosis potentially threatening to the healthy "neighbors"
of a dying cell?
A)
Cell death would usually spread from one cell to the next via paracrine
signals.
B)
Lysosomal enzymes exiting the dying cell would damage surrounding cells.
C)
Bits of membrane from the dying cell could merge with neighboring cells and
bring in foreign receptors.
D)
Neighboring cells would activate immunological responses.
57)
In the nematode C. elegans, ced-9 prevents apoptosis in a normal
cell in which of the following ways?
A)
It prevents the caspase activity of ced-3 and ced-4.
B)
Ced-9 remains inactive until it is signaled by ced-3 and other
caspases.
C)
Ced-9 cleaves to produce ced-3 and ced-4.
D)
Ced-9 prevents blebbing by its action on the cell membrane.
58)
In research on aging (both cellular aging and organismal aging), it has been
found that aged cells do not progress through the cell cycle as they had
previously. Which of the following, if found in cells or organisms as they age,
would provide evidence that this is related to cell signaling?
A)
Growth factor ligands do not bind as efficiently to receptors.
B)
Hormone concentrations decrease.
C)
cAMP levels change very frequently.
D)
Enzymatic activity declines.
59)
Apoptosis involves all but which of the following?
A)
fragmentation of the DNA
B)
activation of cellular enzymes
C)
lysis of the cell
D)
digestion of cellular contents by scavenger cells
60)
An unlabeled signaling diagram for steroid hormones: Fig. 11.8 p. 213, Campbell
8e.
A
steroid hormone, like estrogen, passes through the plasma membrane and binds to
an intracellular protein as shown in the diagram below. This activates a
signal-transduction pathway which results in an increased production of a
specific protein.
Which
of the following statements would explain what would occur as a result of the
signal pathway represented by the diagram?
A)
Transfer RNA (t-RNA) would accumulate in high levels because it is not required
for protein synthesis.
B)
Ribosomal RNA (r-RNA) levels would increase because ribosomes are specific for
the messenger RNA (m-RNA) with which they bind during transcription of the
polypeptide.
C)
DNA levels would increase in the nucleus as a result of the binding of the
hormone-receptor complex with the DNA.
D)
Messenger RNA (m-RNA) levels would increase in order to be translated into the
protein required by the cell.
61)
Which of the following poses the best evidence that cell-signaling pathways
evolved early in the history of life?
A)
Cell-signaling pathways are seen in "primitive" cells such as
bacteria and yeast.
B)
Bacteria and yeast cells signal each other in a process called quorum sensing.
C)
Signal transduction molecules identified in distantly related organisms are
similar.
D)
Most signals in all types of cells are received by cell surface receptors.
62)
Cells that are infected, damaged, or have reached the end of their functional
life span often undergo "programmed cell death." This controlled cell
suicide is called apoptosis. Select the appropriate description of this event
on a cell's life cycle.
A)
Apoptosis is regulated by cell surface receptors that signal when a cell has
reached its density-dependent limits.
B)
During apoptosis, dying cells leak out their contents including digestive
enzymes that also destroy healthy cells.
C)
During apoptosis, cellular agents chop up the DNA and fragment the organelles
and other cytoplasmic components of a cell.
D)
Each cell organelle has protein signals that initiate the breakdown of the
organelle's components which leads to cell death.
Campbell Biology, 10e (Reece)
Chapter 12 The Cell
Cycle
1)
In eukaryotic cells, chromosomes are composed of _____.
A)
DNA and RNA
B)
DNA only
C)
DNA and proteins
D)
DNA and phospholipids
2)
What is the final result of mitosis in a human?
A)
genetically identical 2n somatic cells
B)
genetically different 2n somatic cells
C)
genetically identical 1n somatic cells
D)
genetically identical 2n gamete cells
3)
Starting with a fertilized egg (zygote), a series of five cell divisions would
produce an early embryo with how many cells?
A)
8
B)
16
C)
32
D)
64
4)
If there are 20 duplicated chromosomes in a cell, how many centromeres are
there?
A)
10
B)
20
C)
30
D)
40
5)
Scientists isolate cells in various phases of the cell cycle. They find a group
of cells that have times more DNA than G1 phase cells. The cells of this group are
_____.
times more DNA than G1 phase cells. The cells of this group are
_____.
A)
between the G1 and S phases in the cell cycle
B)
in the G2 phase of the cell cycle
C)
in the M phase of the cell cycle
D)
in the S phase of the cell cycle
6)
The first gap in the cell cycle (G1) corresponds to _____.
A)
normal growth and cell function
B)
the phase in which DNA is being replicated
C)
the beginning of mitosis
D)
the phase between DNA replication and the M phase
7)
The microtubule-organizing center found in animal cells is an identifiable
structure present during all phases of the cell cycle. Specifically, it is
known as the _____.
A)
microtubulere
B)
centrosome
C)
centromere
D)
kinetochore
8)
In human and many other eukaryotic species' cells, the nuclear membrane has to
disappear to permit _____.
A)
cytokinesis
B)
the attachment of microtubules to kinetochores
C)
the splitting of the centrosomes
D)
the disassembly of the nucleolus
9)
The mitotic spindle is a microtubular structure that is involved in _____.
A)
splitting of the cell (cytokinesis) following mitosis
B)
triggering the compaction and condensation of chromosomes
C)
dissolving the nuclear membrane
D)
separation of sister chromatids
10)
Metaphase is characterized by _____.
A)
aligning of chromosomes on the equator
B)
splitting of the centromeres
C)
cytokinesis
D)
separation of sister chromatids
11)
Kinetochore microtubules assist in the process of splitting centromeres by
_____.
A)
using motor proteins to split the centromere at specific arginine residues
B)
creating tension by pulling toward opposite poles
C)
sliding past each other like actin filaments
D)
phosphorylating the centromere, thereby changing its conformation
12)
Some cells have several nuclei per cell. How could such multinucleated cells be
explained?
A)
The cell underwent repeated cytokinesis but no mitosis.
B)
The cell underwent repeated mitosis with simultaneous cytokinesis.
C)
The cell underwent repeated mitosis, but cytokinesis did not occur.
D)
The cell had multiple S phases before it entered mitosis.
13)
How is plant cell cytokinesis different from animal cell cytokinesis?
A)
The contractile filaments found in plant cells are structures composed of
carbohydrates; the cleavage furrow in animal cells is composed of contractile
phospholipids.
B)
Plant cells deposit vesicles containing cell-wall building blocks on the
metaphase plate; animal cells form a cleavage furrow.
C)
The structural proteins of plant cells separate the two cells; in animal cells,
a cell membrane separates the two daughter cells.
D)
Plant cells divide after metaphase but before anaphase; animal cells divide
after anaphase.
14)
FtsZ is a bacterial cytoskeletal protein that forms a contractile ring involved
in bacterial cytokinesis. Its function is analogous to _____.
A)
the cleavage furrow of eukaryotic animal cells
B)
the cell plate of eukaryotic plant cells
C)
the mitotic spindle of eukaryotic cells
D)
the microtubule-organizing center of eukaryotic cells
15)
At which phase are centrioles beginning to move apart in animal cells?
A)
anaphase
B)
prometaphase
C)
metaphase
D)
prophase
16)
If there are 20 centromeres in a cell at anaphase, how many chromosomes are
there in each daughter cell following cytokinesis?
A)
10
B)
20
C)
40
D)
80
17)
Taxol is an anticancer drug extracted from the Pacific yew tree. In animal
cells, Taxol disrupts microtubule formation. Surprisingly, this stops mitosis.
Specifically, Taxol must affect _____.
A)
the structure of the mitotic spindle
B)
anaphase
C)
formation of the centrioles
D)
chromatid assembly
18)
Which of the following are primarily responsible for cytokinesis in plant cells
but not in animal cells?
A)
kinetochores
B)
Golgi-derived vesicles
C)
actin and myosin
D)
centrioles and centromeres
19)
Movement of the chromosomes during anaphase would be most affected by a drug
that prevents _____.
A)
nuclear envelope breakdown
B)
elongation of microtubules
C)
shortening of microtubules
D)
formation of a cleavage furrow
20)
Measurements of the amount of DNA per nucleus were taken on a large number of
cells from a growing fungus. The measured DNA levels ranged from 3 to 6
picograms per nucleus. In which stage of the cell cycle did the nucleus contain
6 picograms of DNA?
A)
G1
B)
S
C)
G2
D)
M
21)
A group of cells is assayed for DNA content immediately following mitosis and
is found to have an average of 8 picograms of DNA per nucleus. How many
picograms would be found at the end of S and the end of G2?
A)
8; 8
B)
8; 16
C)
16; 8
D)
16; 16
22)
The beginning of anaphase is indicated by which of the following?
A)
Chromatids lose their kinetochores.
B)
Cohesin attaches the sister chromatids to each other.
C)
Cohesin is cleaved enzymatically.
D)
Spindle microtubules begin to polymerize.
23)
During which phase of mitosis do the chromatids become chromosomes?
A)
telophase
B)
anaphase
C)
prophase
D)
metaphase
24)
A cleavage furrow is _____.
A)
a ring of vesicles forming a cell plate
B)
the separation of divided prokaryotes
C)
a groove in the plasma membrane between daughter nuclei
D)
the space that is created between two chromatids during anaphase
Use
the following information to answer the questions below.
The
unlettered circle at the top of the figure shows a diploid nucleus with four
chromosomes that have not yet replicated. There are two pairs of homologous
chromosomes, one long and the other short. One haploid set is black, and the
other is gray. The circles labeled A to E show various combinations of these
chromosomes.
25)
What is the correct chromosomal condition at prometaphase of mitosis?
A)
B
B)
C
C)
D
D)
E
26)
What is the correct chromosomal condition for one daughter nucleus at telophase
of mitosis?
A)
B
B)
C
C)
D
D)
E
27)
If the cell whose nuclear material is shown in the accompanying figure
continues toward completion of mitosis, which of the following events would
occur next?
A)
spindle fiber formation
B)
nuclear envelope breakdown
C)
formation of telophase nuclei
D)
synthesis of chromatids
The
following questions are based on the accompanying figure.
28)
In the figure above, G1 is represented by which
numbered part(s) of the cycle?
A)
I or V
B)
II or IV
C)
III only
D)
V only
29)
In the figure above, which number represents DNA synthesis?
A)
I
B)
II
C)
III
D)
IV
30)
In the figure above, at which of the numbered regions would you expect to find
cells at metaphase?
A)
I and IV
B)
II only
C)
III only
D)
IV only
Use
the data in the accompanying table to answer the following questions.
The
data were obtained from a study of the length of time spent in each phase of
the cell cycle by cells of three eukaryotic organisms designated beta, delta,
and gamma.
Minutes
Spent in Cell Cycle Phases
31)
Of the following, the best conclusion concerning the difference between the S
phases for beta and gamma is that _____.
A)
gamma contains more DNA than beta
B)
beta and gamma contain the same amount of DNA
C)
beta cells reproduce asexually
D)
beta is a plant cell and gamma is an animal cell
The
following information applies to the questions below.
Several
organisms, primarily protists, have what are called intermediate mitotic
organization.
32)
These protists are intermediate in what sense?
A)
They reproduce by binary fission in their early stages of development and by
mitosis when they are mature.
B)
They use mitotic division but only have circular chromosomes.
C)
They maintain a nuclear envelope during division.
D)
None of them form spindles.
33)
What is the most probable hypothesis about these intermediate forms of cell
division?
A)
They represent a form of cell reproduction, which must have evolved completely
separately from those of other organisms.
B)
They rely on totally different proteins for the processes they undergo.
C)
They may be more closely related to plant forms that also have unusual mitosis.
D)
They show some but not all of the evolutionary steps toward complete mitosis.
Use
the following information to answer the questions below.
Nucleotides
can be radiolabeled before they are incorporated into newly forming DNA and,
therefore, can be assayed to track their incorporation. In a set of
experiments, a student—faculty research team used labeled T nucleotides and
introduced these into the culture of dividing human cells at specific times.
34)
Which of the following questions might be answered by using the method
described?
A)
How many cells are produced by the culture per hour?
B)
What is the length of the S phase of the cell cycle?
C)
How many picograms of DNA are made per cell cycle?
D)
When do spindle fibers attach to chromosomes?
35)
The research team used their experiments to study the incorporation of labeled
nucleotides into a culture of lymphocytes and found that the lymphocytes
incorporated the labeled nucleotide at a significantly higher level after a
pathogen was introduced into the culture. They concluded that _____.
A)
the presence of the pathogen made the experiments too contaminated to trust the
results
B)
infection causes lymphocytes to divide more rapidly
C)
infection causes cell cultures in general to reproduce more rapidly
D)
infection causes lymphocyte cultures to skip some parts of the cell cycle
36)
Through a microscope, you can see a cell plate beginning to develop across the
middle of a cell and nuclei forming on either side of the cell plate. This cell
is most likely _____.
A)
an animal cell in the process of cytokinesis
B)
a plant cell in the process of cytokinesis
C)
an animal cell in the S phase of the cell cycle
D)
a plant cell in metaphase
37)
Which of the following does NOT occur during mitosis?
A)
condensation of the chromosomes
B)
replication of the DNA
C)
spindle formation
D)
separation of the spindle poles
38)
The drug cytochalasin B blocks the function of actin. Which of the following
aspects of the cell cycle would be most disrupted by cytochalasin B?
A)
spindle formation
B)
spindle attachment to kinetochores
C)
cell elongation during anaphase
D)
cleavage furrow formation and cytokinesis
39)
Motor proteins require which of the following to function in the movement of
chromosomes toward the poles of the mitotic spindle?
A)
intact centromeres
B)
a microtubule-organizing center
C)
ATP as an energy source
D)
synthesis of cohesin
Use
the data in the accompanying table to answer the following questions.
The
data were obtained from a study of the length of time spent in each phase of
the cell cycle by cells of three eukaryotic organisms designated beta, delta,
and gamma.
Minutes
Spent in Cell Cycle Phases
40)
The best conclusion concerning delta is that the cells _____.
A)
contain no DNA.
B)
contain no RNA.
C)
are in the G0 phase.
D)
divide in the G1 phase.
41)
Neurons and some other specialized cells divide infrequently because they
_____.
A)
no longer have active nuclei
B)
have entered into G0
C)
can no longer bind Cdk to cyclin
D)
show a drop in MPF concentration
42)
MPF is a dimer consisting of _____.
A)
a growth factor and mitotic factor
B)
ATP synthetase and a protease
C)
cyclin and tubulin
D)
cyclin and a cyclin-dependent kinase
43)
Cyclin-dependent kinase (Cdk) is _____.
A)
inactive, or "turned off," in the presence of cyclin
B)
present only during the S phase of the cell cycle
C)
the enzyme that catalyzes the attachment of chromosomes to microtubules
D)
an enzyme that attaches phosphate groups to other proteins
44)
What happens if MPF (mitosis-promoting factor) is introduced into immature frog
oocytes that are arrested in G2?
A)
Nothing happens.
B)
The cells undergo meiosis.
C)
The cells enter mitosis.
D)
Cell differentiation is triggered.
45)
Once a cell completes mitosis, molecular division triggers must be turned off.
What happens to MPF during mitosis?
A)
It is completely degraded.
B)
It is exported from the cell.
C)
The cyclin component of MPF is degraded.
D)
The Cdk component of MPF is degraded and exported from the cell.
46)
The M-phase checkpoint ensures that all chromosomes are attached to the mitotic
spindle. If this does not happen, cells would most likely be arrested in _____.
A)
telophase
B)
prophase
C)
prometaphase
D)
metaphase
47)
Which of the following is released by platelets in the vicinity of an injury?
A)
PDGF
B)
MPF
C)
cyclin
D)
Cdk
48)
Which of the following is a protein synthesized at specific times during the
cell cycle that associates with a kinase to form a catalytically active
complex?
A)
PDGF
B)
MPF
C)
cyclin
D)
Cdk
49)
Which of the following is a protein maintained at steady levels throughout the
cell cycle that requires cyclin to become catalytically active?
A)
PDGF
B)
MPF
C)
cyclin
D)
Cdk
50)
Which of the following triggers the cell's passage past the G2 checkpoint into mitosis?
A)
PDGF
B)
MPF
C)
cyclin
D)
Cdk
51)
The cyclin component of MPF is destroyed toward the end of which phase?
A)
G1
B)
S
C)
G2
D)
M
The
following questions are based on the accompanying figure.
52)
In the figure above, MPF reaches its highest concentration during this stage.
A)
I
B)
II
C)
III
D)
IV
53)
Density-dependent inhibition is explained by which of the following?
A)
As cells become more numerous, they begin to squeeze against each other,
restricting their size and ability to produce control factors.
B)
As cells become more numerous, the cell surface proteins of one cell contact
the adjoining cells and they stop dividing.
C)
As cells become more numerous, the protein kinases they produce begin to
compete with each other, such that the proteins produced by one cell
essentially cancel those produced by its neighbor.
D)
As cells become more numerous, the level of waste products increases,
eventually slowing down metabolism.
54)
Besides the ability of some cancer cells to overproliferate, what else could
logically result in a tumor?
A)
changes in the order of cell cycle stages
B)
lack of appropriate cell death
C)
inability to form spindles
D)
inability of chromosomes to meet at the metaphase plate
55)
Anchorage dependence of animal cells in vitro or in vivo depends on which of
the following?
A)
attachment of spindle fibers to centrioles
B)
response of the cell cycle controls to signals from the plasma membrane
C)
the binding of cell-surface phospholipids to those of adjoining cells
D)
response of the cell cycle controls to the binding of cell-surface
phospholipids
56)
A research team began a study of a cultured cell line. Their preliminary
observations showed them that the cell line did not exhibit either
density-dependent inhibition or anchorage dependence. What could they conclude
right away?
A)
The cells are unable to form spindle microtubules.
B)
They have altered the series of cell cycle phases.
C)
The cells show characteristics of tumors.
D)
They were originally derived from an elderly organism.
57)
For a chemotherapeutic drug to be useful for treating cancer cells, which of
the following is most desirable?
A)
It is safe enough to limit all apoptosis.
B)
It does not alter metabolically active cells.
C)
It interferes with cells entering G0.
D)
It interferes with rapidly dividing cells.
58)
Cells from advanced malignant tumors often have very abnormal chromosomes and an
abnormal number of chromosomes. What might explain the association between
malignant tumors and chromosomal abnormalities?
A)
Cancer cells are no longer density-dependent.
B)
Cancer cells are no longer anchorage-dependent.
C)
Cell cycle checkpoints are not in place to stop cells with chromosome
abnormalities.
D)
Transformation introduces new chromosomes into cells.
59)
Exposure of zebrafish nuclei to meiotic cytosol resulted in phosphorylation of
NEP55 and L68 proteins by cyclin-dependent kinase 2. NEP55 is a protein of the
inner nuclear membrane, and L68 is a protein of the nuclear lamina. What is the
most likely role of phosphorylation of these proteins in the process of
mitosis?
A)
They enable the attachment of the spindle microtubules to kinetochore regions
of the centromere.
B)
They are involved in the disassembly and dispersal of the nucleolus.
C)
They are involved in the disassembly of the nuclear envelope.
D)
They assist in the movement of the centrosomes to opposite sides of the
nucleus.
60)
Density-dependent inhibition is a phenomenon in which crowded cells stop
dividing at some optimal density and location. This phenomenon involves binding
of a cell-surface protein to its counterpart on an adjoining cell's surface. A
growth inhibiting signal is sent to both cells, preventing them from dividing.
Certain external physical factors can affect this inhibition mechanism.
Select
the statement that makes a correct prediction about natural phenomena that
could occur during the cell cycle to prevent cell growth.
A)
As cells become more numerous, they begin to squeeze against each other,
restricting their size and ability to allow cell growth.
B)
As cells become more numerous, the protein kinases they produce begin to
compete with each other until only one cell has the proteins necessary for
growth.
C)
As cells become more numerous, the amount of required growth factors and
nutrients per cell becomes insufficient to allow for cell growth.
D)
As cells become more numerous, more and more of them enter the synthesis part
of the cell cycle and duplicate DNA to inhibit cell growth.
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