Content B
6. Membranes
7. Cell-Cell Interaction
8. Energy and Metabolism
9. How Cells Harvest Energy
10. Photosynthesis
PART VI
1. Principal classes of membrane proteins include all
of the following except
A) receptors
B) cell surface markers
C) spectrins
D) transport proteins
2. Which of the following are not components of the
cell membrane?
A) cell surface markers
B) transmembrane proteins
C) interior protein network
D) plasmodesmata
3. To cross the cell membrane, water must
A) squeeze between phospholipid
molecules
B) pass through aquaporins
C) be transported at the expense of ATP
D) be moved by a cotransport system
4. If a cell's contents are greatly hypoosmotic to
the surrounding environment, the cell will probably
A) expand
B) become isotonic
C) burst
D) shrivel
5. The sodium-potassium pump passes
A) more Na+ out than K+ in
B) K+ out and Na+ in on a one-for-one
basis
C) Na+ out and K+ in on a one-for-one
basis
D) K+ and Na+ in the same direction
6. Exocytosis is a process by which cells
A) pass substances out of the cell in
vesicles
B) pass substances out of the cell
through the membrane by osmosis
C) release substances directly into the
extracellular fluid through a pore
D) release substances directly into the
extracellular fluid through a pit
E) identify substances in the
environment
7. A phospholipid has
A) a phosphate group in place of one
fatty acid
B) phosphate groups in place of two
fatty acids
C) phosphate groups in place of three
fatty acids
D) a phosphate group in place of a
carbon in glycerol
E) none of the above
8. Clathrin-coated pits are used to
A) extrude bulk fluids from the cell
B) allow desired molecules directly
into the cytoplasm
C) pass wastes in vesicles to the
outside.
D) pass information into adjacent cells
E) bring desired substances from the
environment into the cell in vesicles
9. A lipid bilayer
A) permits water soluble molecules to
pass through it
B) facilitates the passage of water
soluble molecules through it
C) inhibits the passage of water
soluble substances through it
D) actively transports water soluble
molecules through it
E) is indifferent to the passage of
water molecules through it
10. A cell is recognized by other tissue members as
"self" by its surface
A) glycolipids
B) phosphate groups
C) glycoproteins
D) ketoglutaric acids
E) glycocarbohydrates
11. A net gain of water tends to occur
A) in a hypoosmotic solution from an
isosmotic solution
B) in an isosmotic solution from a
hyperosmotic solution
C) in a hyperosmotic solution from a
hypoosmotic solution
D) in a hypoosmotic solution from a
hyperosmotic solution
E) in one isosmotic solution from
another isosmotic solution of the same composition
12. Red blood cells have a characteristic concave
shape because of
A) spectrin
B) dextrin
C) hemoglobin
D) hemocyanin
E) iron
13. By a mechanism called cotransport
A) sugar moves down its concentration
gradient while sodium moves up its concentration gradient
B) sodium moves outward against is
concentration gradient while sugar moves inward down its concentration gradient
C) sugar and sodium move inward down
their concentration gradient
D) sodium moves inward down its
concentration gradient while sugar moves inward up its concentration gradient
E) sodium and sugar move outward
against their concentration gradient
14. Many surface proteins are anchored by
A) polar amino acids
B) hydrogen bonding amino acids
C) nonpolar fatty acids
D) nonpolar amino acids
E) polar fatty acids
15. Transmembrane proteins are
A) always fixed in position
B) always abundant
C) often not fixed in position
D) never abundant
E) none of the above
16. Cystic fibrosis results from defective ion
channels for
A) Na+
B) Cl-
C) Ca++
D) ClO3-
E) H+
17. Fluidity of phospholipid bilayer is increased by
A) double bonds between carbon atoms in
the fatty acid tails
B) steroid lipids at certain
temperatures
C) poor alignment of the fatty acids
tails
D) cholesterol at certain temperatures
E) all of the above
18. A cell engaged in phagocytosis must be
A) engulfing a live organism
B) acquiring a liquid
C) engulfing a dead organism
D) transporting bulk dissolved nutrients
E) transporting bulk solid material
19. A, B, and O blood groups are marked by surface
A) glycoproteins
B) glycolipids
C) glycocarbohydrates
D) glycerol
E) gluterates
20. In each cycle the sodium-potassium pumps transfer
A) two potassium ions in and two sodium
ions out
B) one sodium ion out and one potassium
ion in
C) three sodium ions out and two
potassium ions in
D) one potassium ion out and two sodium
ions in
E) three sodium ions in and two
potassium ions out
21. ____________________ are transported by a
particular carrier or pass through a particular channel.
A) All water soluble ions or molecules
B) Certain water soluble molecules or
ions
C) All insoluble molecules or ions
D) Certain insoluble ions or molecules
E) Only the smallest molecules or ions
22. Equilibrium is reached in an aqueous solution
when
A) random motion stops
B) water molecules and dissolved
molecules are moving at the same rate
C) the dissolved molecules or ions are
equally distributed throughout the solution
D) molecular motion stops
E) there are the same number of water
molecules as dissolved molecules
23. Substances transported by facilitated diffusion
A) move passively through specific
channels from an area of greater concentration to one of lower concentration
B) are limited to solvents
C) must have movements coupled to those
of other substances
D) may flow to a region of higher
concentration by the expenditure of energy
E) are restricted to only one direction
through the membrane
24. In a lipid bilayer the lipids have
A) their water repelling heads facing
inward
B) their water repelling tails facing
inward
C) their hydrogen bond forming heads
facing inward
D) their hydrogen bond forming tails
facing inward
E) no relationship to water
25. A lipid bilayer is held together by
A) surface tension
B) double bonds in their fatty acid
tails
C) the attraction of the phospholipid
heads to each other
D) hydrogen bonding with water
E) the electrostatic attraction of
phosphate groups for each other
26. The glycocalyx is a "sugar coating" on
the surface of a cell resulting from the presence of polysaccharides on
glycolipids and glycoproteins embedded in the outer layer of the plasma
membrane.
A) True
B) False
27. Threonine, an amino acid, and arabinose, a
monosaccharide, cross the cell membrane down their concentration gradients by:
A) diffusion.
B) endocytosis.
C) phosphorylation.
D) facilitated diffusion.
E) osmosis.
28. A contractile vacuole is an organelle that pumps
excess water out of many freshwater protozoan cells. A freshwater protozoan was
placed in solution A and observed to form contractile vacuoles at a rate of 11
per minute. The same protozoan was then placed in solution B and observed to
form contractile vacuoles at a rate of 4 per minute. Based on this information,
which of the following statements is correct?
A) Solution A is hyperosmotic to
solution B.
B) Solutions A and B are isosmotic.
C) Solution B is hyperosmotic to
solution A.
D) Solutions A and B are isosmotic to
the protozoan cell.
E) Both a and b.
29. The net movement of uncharged, polar molecules
across a semipermeable membrane from a low concentration to a high
concentration occurs by facilitated diffusion.
A) True
B) False
30. The membrane transport mechanism used when an
amoeba engulfs a bacterial cell is called:
A) exocytosis
B) pinocytosis
C) facilitated diffusion
D) active transport
E) phagocytosis
31. Continuing from the previous question, once the
bacterial cell has been digested, the amoeba will dispose of indigestible
materials by which of the following processes?
A) facilitated diffusion
B) through gated channels in membrane
proteins
C) exocytosis
D) active transport
E) by any of the above processes
32. ATP is required in the transport of
A) water molecules
B) all molecules across a membrane
C) molecules to areas of lower
concentrations
D) molecules to areas of higher
concentrations
E) molecules through a protein channel
33. The sodium-potassium pump establishes
concentration gradients
A) of higher sodium concentrations
inside the cell and higher potassium concentrations outside the cell
B) of sodium and potassium but the area
of their concentrations (inside or outside) depends on the needs of the cell
C) of higher potassium concentrations inside the cell and
higher sodium concentrations outside the cell
D) of ATP inside the cell where it is needed
E) by pumping sodium outside the cell
and potassium is cotransported out as well
34. In cotransport processes, sugars can be brought
into the cell against their concentrations gradients
A) because ATP powers the pump that
brings them in
B) because they follow sodium ions into
the cell which are traveling down their concentration gradients
C) because they follow potassium in
through the sodium-potassium pump
D) through endocytosis
E) sugar enters the cell by all of the
processes listed above
35. The methods of membrane transport that don't
require protein channels or carriers are
A) osmosis
B) diffusion
C) phagocytosis
D) exocytosis
E) all of the above
PART VII
1. Synaptic signaling involves
A) endocrine signals
B) paracrine signals
C) autocrine signals
D) neurotransmitters
2. Characteristics of intracellular receptors that regulate gene
transcription include all of the following except
A) a DNA binding site
B) an extracellular binding site
C) a transcription activating domain
D) may be signaled by lipid soluble
molecules
3. Cell surface receptors may be any of the following except
A) G protein linked
B) enzymic receptors
C) single-pass transmembrane proteins
for neurotransmitters
D) chemically-gated ion channels
4. In the cAMP pathway, the G protein stimulates
A) phospholipase C
B) adenylyl cyclase
C) the endoplasmic reticulum
D) calmodulin
5. The ____ surrounds the cell like a belt, preventing the passage
of substances between the cells.
A) gap junction
B) desmosome
C) hemidesmosome
D) tight junction
6. In most cases protein kinases
A) hydrolyze proteins
B) polymerize amino acids
C) stimulate adenylyl cyclase
D) bind cGMP
E) add phosphate groups to proteins
7. The receptor for nitric oxide (NO) is
A) intercellular
B) intracellular
C) extracellular
D) ultracellular
E) unicellular
8. In desmosomes, cadherins link to _______________ of an adjacent
cell.
A) integrins
B) connexons
C) ras proteins
D) intermediate filaments
E) plasmodesmata
9. Which of the following are NOT involved in enzyme activation?
A) A-kinase
B) P nucleic acid
C) cAMP
D) nitric oxide
E) G protein
10. ________ junctions may protect a damaged cell through chemical
gating.
A) Tight
B) Gap
C) Adherens
D) Occluding
E) Macular
11. Narrow gaps between nerve cells through which paracrine signals
travel are called
A) desmosomes
B) calmodulins
C) synapses
D) integrins
E) maculae
12. _______________ is a common second messenger.
A) cAMP
B) cGTP
C) cMHC
D) cATP
E) cRNA
13. Paracrine signals
A) are long-lived with widespread
effects
B) are short-lived, but with widespread
effects due to cascades
C) are long-lived, but are acting
locally
D) are short-lived with local effects
E) such as neurotransmitters, function
only intracellularly
14. In anchoring junctions, cadherins are linked to
A) actin filaments in the cell's
cytoskeleton
B) cell walls of adjacent cells in
plants
C) connexons of its own and adjacent
cells
D) extracellular matrices of adjacent
cells
E) intracellular integrins of most
cells
15. Intracellular receptors include those for
A) progesterone
B) vitamin D
C) cortisol
D) thyroid hormone
E) all of the above
16. Adherens junctions may involve
A) extracellular matrix
B) integrins
C) actin filaments
D) all of the above
E) none of the above
17. With respect to the plasma membrane, most enzymic receptors are
A) entirely internal
B) seven pass
C) entirely on the surface
D) multipass
E) single pass
18. A single-pass protein that acts as a "self" marker is
A) GTP
B) MHC
C) GMP
D) MCA
E) ADP
19. Binding of epinephrin to a G protein-linked receptor causes
adenylyl cyclase to produce large amounts of
A) A-kinase
B) G protein
C) phospholipase C
D) inositol triphosphate
E) cAMP
20. Cell signals with short-lived local effects are called
_______________
A) paracrine
B) apocrine
C) merocrine
D) holocrine
E) none of the above
21. Desmosomes are associated with ____________ junctions.
A) adherens
B) tight
C) anchoring
D) communicating
E) lymphomas
22. One protein kinase cascade begins with the phosphorylation of
the
A) tap protein
B) gat protein
C) sat protein
D) ras protein
E) sap protein
23. Plasmodesmata
A) encircle cells of a tight junction
like a belt
B) connect to intermediate fibers of
the cytoskeleton
C) connect the cytoplasm of one plant
cell to that of another
D) connect actin fibers of one cell to
the extracellular matrix of another
E) is the name given to desmosomes of
plant cells
24. The signalling molecules that travel the farthest are
A) endocrine
B) paracrine
C) neurotransmitter
D) intracellular
25. When a signal molecule arrives at a G protein-linked receptor,
the G protein
A) becomes deactivated
B) binds to the signal molecule
C) becomes activated
D) binds with a Ca++
E) binds with calmodulin
26. Cells interact through the actions of chemical signals which either
bind to receptors on the membrane or
A) pass through the plasma membrane
B) trigger responses from inside the
cell
C) bind to intracellular receptors
D) activate receptors that bind to DNA
E) all of the above
27. Cell junctions that prevent small molecules from passing in
between two cells are called
A) gap junctions
B) tight junctions
C) adhesions
D) plasmodesmata
E) all of the above
28. In some tissues subject to mechanical stress, special junctions
called _______________ connect the cytoskeletons of adjacent cells.
A) cadherin junctions
B) tight junctions
C) stress junctions
D) anchoring junctions
E) gap junctions
29. Gap junctions are formed by
A) the fusion of plasma membranes to
form a single membrane
B) the insertion of protein complexes
that form tunnels between cells
C) protein hooks that extend into the
membrane of adjacent cells
D) gaps in the cell wall of plants
E) none of the above
30. Plasmodesmata occur in
A) bacterial cells
B) all eukaryotic cells
C) plant cells
D) animal cells
E) the nucleus of the cell
31. A _______________ is a type of adhering junction between animal
cells.
A) tight junction
B) plasmodesma
C) chemical synapse
D) gap junction
E) c and d, but not a and b
32. Protein kinases are enzymes that stimulate the production of
hormones.
A) True
B) False
33. Hormones are relatively long lived signals that travel
throughout the body. This type of signalling is called
A) paracrine signalling
B) synaptic signalling
C) autocrine signalling
D) endocrine signalling
E) direct contact
34. All of the following statements apply to G proteins except
A) G proteins transmit a signal from the
cell surface to the interior of the cell
B) all G proteins have a similar
structure
C) G proteins do not use second
messengers but transmit the signal directly into the nucleus
D) G proteins act to amplify the signal
creating a cascade response in the cell
E) G proteins underlie the actions of
many medications
35. Receptors that are recognized by the immune system are
A) immunoglobulins
B) MHC proteins
C) T receptor
D) B receptor
E) all of the above
PART VIII
1. The second law of thermodynamics essentially says
A) heat is energy
B) motion energy converts to heat
energy
C) at the atomic level, motion is
continuous
D) entropy increases
2. The energy required to destabilize existing
chemical bonds is called ____ energy.
A) activation
B) destabilization
C) kinetic
D) free
3. If DG is said to be positive, it means
A) H is lower
B) reactants contain more energy than
the product does
C) S in the system is higher
D) products of the reaction contain more
energy than the reactants
4. Which of the following is uncharacteristic of ATP?
A) It is formed by attaching a phosphate
group to ADP with a high-energy bond.
B) In most reactions involving ATP,
only the outer, high-energy bond is hydrolized.
C) It is a good long-term energy
storage molecule.
D) When dephosphorylated, ATP becomes
ADP.
5. The most primitive form of metabolism is
A) glycolysis
B) oxygen-forming photosynthesis
C) the degradation of organic molecules
with the released energy stored in ATP
D) anaerobic respiration
6. The First Law of Thermodynamics states that energy
can be
A) created
B) destroyed
C) converted
D) all of the above
E) none of the above
7. The universal energy currency for all cells is
A) ATP
B) NAD+
C) ADP
D) enzymes
E) O2
8. Enzymes
A) make endergonic reactions proceed
spontaneously
B) lower the activation energy of a
reaction
C) are not very specific in their
choice of substrates
D) are needed in large quantities
because they are used up during catalysis
E) none of the above
9. To what category of macromolecules do most enzymes
belong?
A) carbohydrates
B) lipids
C) steroids
D) nucleic acids
E) proteins
10. NAD+ is a(n)
A) enzyme
B) coenzyme
C) active site
D) high-energy bond
E) allosteric activator
11. Which of the following is a reduced compound?
A) CO2
B) O2
C) N2
D) NAD+
E) NADH
12. In an endergonic reaction,
A) the reactants contain less free
energy than the products
B) the reactants contain more free
energy than the products
C) no activation energy is required
D) catalysis cannot occur
E) substrates outnumber enzymes
13. The energy of random molecular motion is called
A) heat
B) free energy
C) enthalpy
D) potential energy
E) activation energy
14. The energy available to do work in a system is
called
A) entropy
B) activation energy
C) thermodynamics
D) free energy
E) heat
15. The initial steps in breaking down glucose are
called
A) nitrogen fixation
B) glycolysis
C) chemiosmosis
D) intramolecular catalysis
E) intermolecular catalysis
16. A catalyst will make a reaction
A) stop
B) slow down
C) speed up
D) go in a different direction
E) you can never tell
17. When molecules are reduced they gain
A) energy
B) electrons
C) hydrogen protons
D) all of the above
E) none of the above
18. Which of the following statements about enzymes
is true?
A) some substrates can make enzymes
change shape slightly
B) all enzymes have the same pH optimum
C) the active sites of all enzymes have
the same three-dimensional shape
D) all of the above
E) none of the above
19. Cofactors
A) break hydrogen bonds in proteins
B) help facilitate enzyme activity
C) increase activation energy
D) are very rare in living organisms
E) are linked to ATP by high-energy
bonds
20. How much energy is released when one of the
high-energy bonds in ATP is broken?
A) 730 cal/mole
B) 7.3 cal/mole
C) 7.3 kcal/mole
D) 73 kcal/mole
E) 730 kcal/mole
21. Consider the hypothetical biochemical pathway H
-- I -- J-- K-- L. Which step most likely evolved first?
A) H -- I
B) I -- J
C) I -- H
D) J -- K
E) K -- L
22. Why do drastic changes in the temperature or pH
of a system alter enzyme activity?
A) they change the three-dimensional
shape of the enzyme
B) they disrupt hydrogen and ionic
bonds in the enzyme
C) they disrupt hydrophobic
interactions in the enzyme
D) all of the above
E) none of the above
23. The loss of an electron by a molecule is called
A) oxidation
B) reduction
C) induced fit
D) enthalpy
E) allosteric inhibition
24. In the chemical equation G = H - TS, the term G
stands for
A) entropy
B) the reactants
C) enthalpy
D) free energy
E) the products
25. Enzyme B requires Zn2+ in order to catalyze the
conversion of substrate X. The zinc is best identified as a(n):
A) coenzyme
B) cofactor
C) substrate
D) product
E) enzyme
26. The next two questions refer to the following
chemical reaction that is catalyzed by the enzyme malic dehydrogenase: malic
acid + NAD+ -----> oxaloacetic acid + NADH + H+ delta G = +7.1 kcal.
Which of the following statements are true of this
reaction?
A) Malic acid is reduced to oxaloacetic
acid.
B) b. The bonds within the products are
more stable than those within the substrates.
C) The reaction is endergonic.
D) Entropy is increasing.
E) Both b and c, but not a and d.
27. NAD+
A) is being reduced.
B) is a coenzyme.
C) is an oxidizing agent.
D) all of the above.
E) a and b, but not c.
28. In the malate dehydrogenase reaction given above,
NAD+ is a reducing agent.
A) True
B) False
29. Which of the following must be true for a
reaction to occur spontaneously?
A) delta G must be negative
B) delta H must be negative
C) delta S must be positive
D) delta G must be positive
E) b, c, and d, but not a
30. Continuing with question 5, this reaction would
occur spontaneously.
A) True
B) False
31. Redox reactions (oxidation-reduction)
A) do not occur in living systems
B) require the presence of oxygen
C) involve the loss of electrons termed
oxidation
D) involve the gaining of energy by an
oxidized substance
E) both a and b
32. The actions of an enzyme can be affected by all
of the following except
A) p/PH
B) temperature
C) allosteric inhibitors
D) availability ATP
E) cofactors
33. Which of the following are mismatched
A) anabolic reactions-expend energy
B) reduction-gain of an electron
C) endergonic reaction-anabolism
D) exergonic reaction-catabolism
E) activation energy-entropy
PART IX
1. When energy-depleted elements associated with a
proton are accepted by an organic molecule, the process is called
A) fermentation
B) anaerobic
C) aerobic
D) catabolism
2. An example of anaerobic would be
A) production of sulfates from H2S
B) production of methane by methanogens
C) glycolysis by purple bacteria
D) utilization of methane by methanogens
3. The end product of glycolysis is
A) NADH
B) acetyl-CoA
C) lactate
D) pyruvate
4. The final output of the Krebs cycle includes all
of the following except
A) NADP
B) FADH2
C) ATP
D) CO2
5. The usefulness of fermentation as a means of
deriving energy is limited because
A) it cannot generate enough ATP
B) it produces too much NH2
C) the end products are toxic to the
producer
D) it uses more energy than it produces
6. Which of the following is not a product of
fermentation?
A) CO2
B) O2
C) ethanol
D) lactate
E) all of the above are products of
fermentation
7. What substance is produced by the oxidation of
pyruvate and feeds into the citric acid cycle?
A) pyruvate
B) glucose
C) acetyl-CoA
D) O2
E) CO2
8. Glycolysis has an efficiency level of
approximately
A) 2%
B) 3.5%
C) 21.5%
D) 50%
E) 78.5%
9. Hans Krebs discovered (worked out the details of)
A) glycolysis
B) fermentation
C) the oxidation of pyruvate
D) the citric acid cycle
E) electron transport and chemiosmosis
10. Oxidative respiration in eukaryotes has an
efficiency level of approximately
A) 2%
B) 63%
C) 14%
D) 36%
E) 32%
11. In aerobic cellular respiration, which generates
more ATP, substrate-level phosphorylation or chemiosmosis?
A) substrate-level phosphorylation
B) chemiosmosis
C) both generate the same amount of ATP
D) neither generates any ATP
12. What role does O2 play in aerobic respiration?
A) it plays no role
B) it combines with acetyl-CoA at the
start of the Krebs cycle
C) it is given off as a by-product
during the oxidation of pyruvate
D) it combines with H2O to help drive
the formation of ATP
E) it is the final electron acceptor at
the end of the electron transport chain
13. During aerobic respiration, FADH2 is produced in
A) glycolysis
B) the oxidation of pyruvate
C) the Krebs cycle
D) the electron transport chain
E) fermentation
14. NADH is produced during
A) glycolysis
B) the oxidation of pyruvate
C) the Krebs cycle
D) all of the above
E) none of the above
15. Organisms that do not have the ability to produce
or synthesize their own food are called
A) anaerobic
B) autotrophs
C) exergonic
D) catabolic
E) heterotrophs
16. The proper sequence of stages in glycolysis is
A) glucose priming, cleavage and
rearrangement, oxidation, ATP generation
B) cleavage and rearrangement, glucose
priming, ATP generation, oxidation
C) glucose priming, oxidation, cleavage
and rearrangement, ATP generation
D) ATP generation, oxidation, glucose
priming, cleavage and rearrangement
E) oxidation, cleavage and
rearrangement, ATP generation, glucose priming
17. During what stage of cellular respiration is the
most ATP synthesized?
A) glycolysis
B) oxidation of pyruvate
C) Krebs cycle
D) fermentation
E) chemiosmosis
18. Catabolic processes
A) make complex molecules from simpler
ones
B) break complex molecules into simpler
ones
C) occur only in autotrophs
D) occur only in heterotrophs
E) none of the above
19. What substance is regenerated by fermentation?
A) O2
B) NAD+
C) acetyl-CoA
D) ATP
E) glucose
20. Which of the following is a multienzyme complex?
A) glyceraldehyde-3-phosphate (G3P)
B) NAD+
C) FAD+
D) pyruvate dehydrogenase
E) all of the above
21. During chemiosmosis in aerobic respiration,
protons are pumped
A) out of the cell
B) out of the mitochondria into the
cell cytoplasm
C) out of the mitochondrial matrix into
the outer compartment of the mitochondria
D) out of the cell cytoplasm into the
matrix of the mitochondria
E) out of the nucleus and into the
mitochondria
22. Each molecule of FADH2 results in the production
of how many ATP molecules during aerobic respiration?
A) 2
B) 3
C) 4
D) 18
E) 36
23. Which of the following organisms carries out
cellular respiration?
A) a corn plant
B) a dog
C) a yeast
D) a bacterium
E) all of the above
24. Oxidizing which of the following substances
yields the most energy?
A) proteins
B) glucose
C) fatty acids
D) alcohol
E) water
25. The oxidation of glucose to two molecules each of
pyruvate, ATP, and NADH is called ________ and occurs in the ________.
A) glycolysis; cytoplasm
B) fermentation; cytoplasm
C) the Krebs cycle; matrix of the
mitochondrion
D) anaerobic respiration; cytoplasm
E) the respiratory electron transport
chain; cristae of the mitochondrion
26. A cell culture was supplied with radioactively
labeled O2. The cells were monitored. In a few minutes the radioactive oxygen
atoms were present in which of the following compounds:
A) carbon dioxide
B) NADH and FADH2
C) water
D) ATP
E) lactic acid
27. During respiration, NADH donates two electrons to
the carrier know as ubiquinone. When this happens, ubiquinone:
A) becomes oxidized.
B) passes the electrons directly to O2
which is reduced to water.
C) pumps protons across the inner
mitochondrial membrane.
D) all of the above.
E) a and b, but not c.
28. The final electron acceptor in lactic acid
fermentation is:
A) NAD+
B) pyruvate
C) O2
D) lactic acid
E) ATP
29. Under normal conditions, as electrons flow down
the electron transport chain of the mitochondria:
A) NADH and FADH2 are oxidized.
B) the pH of the matrix increases.
C) the electrons lose free energy.
D) an electrochemical gradient is
formed.
E) all of the above.
30. Pyruvate is oxidized when oxygen is present.
A) True
B) False
31. During the oxidation of glucose, a net gain of
ATP only occurs under aerobic conditions.
A) True
B) False
32. ATP can be formed through substrate-level
phosphorylation and this process requires
A) an input of energy
B) a high-energy phosphate group that
is transferred directly to ADP
C) a concentration gradient of protons
D) the protein ATPsynthase
E) all of the above
33. Proteins and fats can be nutritional sources of
energy provided that
A) they are converted into glucose
B) the enter their own pathways that
are separate from the glucose metabolic pathways
C) they are degraded completely into
atoms before entering a pathway
D) they are modified so that they can
enter the glucose metabolic pathways
E) both b and c
34. ATP formation by glycolysis
A) occurs through aerobic respiration
B) is an extremely efficient method of
acquiring energy by the cell
C) requires oxygen
D) involves substrate-level
phosphorylation
E) both a and c
35. Under which condition would you expect the
mitochondrial proton gradient to be highest and therefore ATP synthesis to
proceed?
A) pyruvate (present)-oxygen
(present)-ATP levels (high)
B) pyruvate (present)-oxygen
(present)-ATP levels (low)
C) pyruvate (present)-oxygen
(absent)-ATP levels (high)
D) pyruvate (absent)-oxygen
(present)-ATP levels (low)
E) pyruvate (absent)-oxygen
(absent)-ATP levels (high)
36. In the course of the cell's breakdown of one
glucose molecule, the mitochondrion takes up certain reactants and releases
certain products. Indicate some of these reactants and products below by
selecting the best choice from each numbered set of letters: REACTANTS
(materials entering)
A) 6 carbon dioxide molecules
B) 2 pyruvates
C) 1 glucose
D) 2 lactates
E) 2 PEP
PART X
1. The light reaction of photosynthesis does not
include
A) chemiosmosis
B) oxygen liberation
C) charge separation
D) electron transport
2. The final product of the Calvin cycle is
A) RuPB
B) PGA
C) ATP
D) G3P
3. Photosynthesis takes place in the membranes of
small sacs called
A) thylakoids
B) grana
C) photosystems
D) photons
4. The dark reaction in photosynthesis is limited by
A) CO2, temperature, and light
B) CO2, light, and water
C) water, temperature, and CO2
D) oxygen, water, and temperature
5. Colors of light most useful in photosynthesis are
A) green, yellow, and orange
B) red, violet, and blue
C) infrared, red, and yellow
D) red, white, and blue
6. During what stage of photosynthesis is O2
produced?
A) cyclic photophosphorylation
B) the light-dependent reactions
involving photosystems I and II
C) carbon fixation
D) the Krebs cycle
E) O2 is not produced during photosynthesis
7. The pigment molecules responsible for
photosynthesis are located in the
A) mitochondria
B) cytoplasm of the cell
C) stroma of the chloroplast
D) thylakoid membrane of the chloroplast
E) all of the above
8. Both carotenoids and chlorophylls
A) are pigments
B) absorb photons of all energy ranges
C) contain porphyrin rings
D) all of the above
E) none of the above
9. Which of the following is the correct sequence for
the movement of electrons during the light-dependent reactions of plants?
A) P680 à P700 à water à NADP+
B) water à P700 à NADP+à P680
C) P700 à P680 à NADP+à water
D) P680 à water à P700 à NADP+
E) water à P680 à P700 à NADP+
10. What pigment is used in human vision?
A) chlorophyll a
B) beta-carotene
C) retinal
D) vitamin A
E) ferredoxin
11. During what stage of photosynthesis are ATP and
NADPH converted to ADP + Pi and NADP+?
A) the light-dependent reactions
B) the light-independent reactions
C) both of the above
D) none of the above
12. Water vapor exits and CO2 enters a leaf through
the
A) stomata
B) grana
C) porphyrin rings
D) photons
E) stroma
13. Which of the following organisms have the
greatest problem with photorespiration?
A) C4 plants
B) heterotrophs
C) C3 plants
D) CAM plants
E) purple sulfur bacteria
14. What energy-rich organic compound is produced as
a result of the Calvin cycle?
A) NADPH
B) CO2
C) ATP
D) H2O
E) glucose
15. High-energy photons
A) have long wavelengths
B) have short wavelengths
C) are more likely to produce red light
than blue light
D) cannot be absorbed
16. Light that is visible to humans occupies what
part of the electromagnetic spectrum?
A) the entire upper half
B) the entire lower half
C) a small portion in the middle
D) the entire spectrum
E) visible light is not part of the
electromagnetic spectrum
17. During photosynthesis, photons raise electrons to
higher energy levels. These excited electrons belong to what compound?
A) H2O
B) ATP
C) RuBP
D) glucose
E) chlorophyll
18. Which of the following occurs during the
light-dependent reactions of plants?
A) electron transport
B) chemiosmosis
C) splitting of water
D) all of the above
E) none of the above
19. The oxygen that is released as O2 during
photosynthesis came from _____________ molecules.
A) carbon dioxide
B) water
C) glucose
D) chlorophyll
E) ATP
20. Compared to retinal, chlorophyll can be described
as a pigment that has a
A) narrow absorption range but high efficiency
B) narrow absorption range but low
efficiency
C) wide absorption range but high
efficiency
D) wide absorption range but low
efficiency
21. The earliest photosynthesizers probably used what
as a source of hydrogen?
A) H2S
B) H2O
C) CO2
D) C6H12O6
22. How many carbon atoms are in a molecule of RuBP?
A) zero
B) one
C) two
D) three
E) five
23. Which of the following is mismatched?
A) Photosystem I - uses the P700
molecule in its photocenter
B) PGA - a 3-carbon compound
C) antenna complex - contains hundreds
of pigment molecules
D) CAM plants - open their stomata
during the day and close them at night to avoid photorespiration
E) C4 plants - expend ATP to
concentrate CO2 in bundle-sheath cells to avoid photorespiration
24. Which of the following statements about
photosynthesis is true?
A) the light-dependent reactions can
occur only in the light, the light-independent reactions only in the dark
B) photorespiration is more efficient
at producing glucose than is photosynthesis
C) the light-dependent reactions
produce the energy-rich compounds that are used to run the light-independent
reactions
D) all of the above are true
25. Which of the following statements accurately
describes the relationship between photosynthesis and cellular respiration?
A) photosynthesis occurs only in
autotrophs; cellular respiration occurs only in heterotrophs
B) photosynthesis uses solar energy to
convert inorganics to energy-rich organics; respiration breaks down energy-rich
organics to synthesize ATP
C) photosynthesis involves the
oxidation of glucose; respiration involves the reduction of CO2
D) the primary function of
photosynthesis is to use solar energy to synthesize ATP; the primary function
of cellular respiration is to break down ATP and release energy
E) photosynthesis and cellular
respiration occur in separate, specialized organelles; the two processes cannot
occur in the same cell at the same time
26. In sulfur bacteria, how many pigment electrons
must get transported during cyclic photophosphorylation to produce one molecule
of ATP?
A) one
B) two
C) three
D) four
E) five
27. Production of one molecule of
3-phosphoglyceraldehyde requires how many turns of the Calvin cycle?
A) 1
B) 2
C) 3
D) 6
E) 12
28. To reduce six molecules of carbon dioxide to
glucose via photosynthesis, how many molecules of NADPH and ATP are required?
A) 6 NADPH and 6 ATP
B) 12 NADPH and 12 ATP
C) 12 NADPH and 18 ATP
D) 18 NADPH and 12 ATP
E) 24 NADPH and 18 ATP
29. The primary form of sugar transported from the
site of photosynthesis to the rest of the plant is:
A) glyceraldehyde 3-phosphate
B) glucose
C) fructose
D) ribulose 1,5-bisphosphate
E) sucrose
30. Rubisco:
A) catalyzes the carboxylation of CO2 to
ribulose 1,5-bisphosphate.
B) initiates photorespiration when the
CO2/O2 ratio is low.
C) catalyzes the reduction of two
molecules of PGAL to form glucose.
D) all of the above (a-c).
E) a and b, but not c.
31. The immediate products of C3 and C4
photosynthesis are, respectfully:
A) ribulose 1,5-bisphosphate; malic acid
B) malate; carbon dioxide
C) 3-phosphoglycerate; oxaloacetic acid
D) glyceraldehyde 3-phosphate;
phospho-enol-pyruvate (PEP)
E) malic acid; glucose
32. Light-driven electron transport in the
chloroplast pumps H+ into the intermembrane space between the outer and inner
membranes.
A) True
B) False
33. CO2 fixation occurs within the stroma.
A) True
B) False
34. If you know the absorption spectrum of a pigment,
you can predict the pigment's color.
A) True
B) False
35. For every CO2 molecule fixed by photosynthesis,
one molecule of O2 is produced.
A) True
B) False
36. Light is required for the light dependent
reactions because
A) it is the source for electrons
B) it splits the water molecule
C) it energizes electrons in the
reaction center
D) it splits ATP molecules which
generates the energy necessary to power the light independent reactions
E) none of the above
