Studied by 21 people
University of Cincinnati, Dr. Mosley, Spring 2024
Which of the following statements is
true about hypertonic solutions?
a. They have a higher solute
concentration than the cell.
b. They cause cells to swell.
c. They have no effect on cells.
d. They have a lower water
concentration than the cell.
a. They have a higher solute
concentration than the cell.
How does the fluid mosaic model
explain the structure of the plasma
membrane?
a. It describes the membrane as
a rigid structure with
proteins embedded in a fluid
lipid matrix
b. It portrays the membrane as
a dynamic structure with
proteins and lipids free to
move laterally
c. It suggests that the
membrane is composed of a
static arrangement of
proteins and carbohydrates
d. None of the above
b. It portrays the membrane as
a dynamic structure with
proteins and lipids free to
move laterally
In which type of reaction is free
energy released, and products have
less free energy than the reactants?
a. Endergonic
b. Exergonic
c. Anabolic
d. Catabolic
b. Exergonic
What type of inhibitor binds to an
enzyme at a site other than the
active site, altering the enzyme's
conformation and activity?
a. Competitive inhibitor
b. Noncompetitive inhibitor
c. Allosteric inhibitor
d. Covalent inhibitor
b. Noncompetitive inhibitor
Which enzyme catalyzes the
conversion of glucose to glucose-6-
phosphate in the first step of
glycolysis, trapping glucose in the
cell?
a. Phosphofructokinase
b. Hexokinase
c. Aldolase
d. Isomerase
b. Hexokinase
The sodium-potassium pump
exchanges sodium ions for
potassium ions at a ratio of:
a. 1:1
b. 2:2
c. 3:2
d. 2:3
c. 3:2
During each cycle of the sodium-potassium pump, how many phosphate groups are hydrolyzed
from ATP?
a. 0
b. 1
c. 2
d. 3
b. 1
What is the main driving force for
the movement of water through a
selectively permeable membrane in
osmosis?
a. Concentration of water
b. Concentration of solutes
c. Voltage difference
d. Temperature
b. Concentration of solutes
Which type of transport is
responsible for moving large
particles or macromolecules into the
cell by forming vesicles?
a. Active transport
b. Endocytosis
c. Exocytosis
d. Facilitated diffusion
b. Endocytosis
Which type of regulation occurs
when a product of a metabolic
pathway inhibits an enzyme earlier
in the pathway?
a. Positive Feedback
b. Negative Feedback
c. Allosteric Regulation
d. Competitive Inhibition
b. Negative Feedback
What is the main function of the
phosphofructokinase enzyme in
glycolysis?
a. To phosphorylate fructose1,6-bisphosphate
b. To reduce NAD+ to NADH
c. To catalyze the conversion of
pyruvate to acetyl-CoA
d. To pump protons into the
mitochondria
a. To phosphorylate fructose1,6-bisphosphate
Which enzyme catalyzes the
dephosphorylation of
phosphoenolpyruvate (PEP) to
pyruvate in glycolysis?
a. Hexokinase
b. Phosphofructokinase
c. Pyruvate kinase
d. ATP synthase
c. Pyruvate kinase
Which of the following statements
about enzymes is true?
a. Enzymes are consumed
during chemical reactions.
b. Enzymes alter the
equilibrium of a chemical
reaction.
c. Enzymes lower the activation
energy of a reaction.
d. Enzymes only work at or near
neutral pH levels.
c. Enzymes lower the activation energy of a reaction.
The Gibbs free energy change for a
chemical reaction is -30 kJ/mol.
What can be said about the
spontaneity of the reaction?
a. The reaction is nonspontaneous.
b. The reaction is spontaneous.
c. The reaction is at
equilibrium.
d. The reaction has no change
in energy.
b. The reaction is spontaneous.
Which gas is produced as a byproduct of the Krebs cycle?
a. Oxygen
b. Carbon dioxide
c. Nitrogen
d. Hydrogen
b. Carbon dioxide
According to the second law of
thermodynamics, what does the
term "entropy" refer to?
a. The energy available to do
work
b. The measure of disorder or
randomness in a system
c. The total energy of a closed
system
d. The amount of heat energy
produced during a reaction
b. The measure of disorder or
randomness in a system
Which statement about membrane
fluidity is accurate?
a. Saturated lipids increase
membrane fluidity
b. Lower temperature
decreases membrane fluidity
c. Higher temperature
decreases membrane fluidity
d. Unsaturated lipids make the
membrane less fluid
b. Lower temperature
decreases membrane fluidity
What is the role of NADH in
glycolysis?
a. It is a substrate for the
reaction.
b. It carries electrons to the
electron transport chain.
c. It is used to produce glucose.
d. It is a waste product.
b. It carries electrons to the
electron transport chain.
What is the primary role of the Krebs
cycle in cellular respiration?
a. To produce ATP directly
b. To convert glucose to
pyruvate
c. To transport electrons to the
electron transport chain
d. To break down fats for
energy
c. To transport electrons to the
electron transport chain
In pyruvate oxidation, which of the
following is a product of the
metabolic pathway per glucose
molecule?
a. 2 ATP
b. 3 CO2
c. 2 NADPH
d. none of the above
d. none of the above
Coupled transport in cell
membranes involves the
simultaneous movement of two
different substances. Which of the
following best describes symport, a
type of coupled transport?
a. Both substances move in the
same direction, both into or
out of the cell.
b. One substance moves into
the cell while the other
moves out of the cell.
c. Both substances move in
opposite directions, either
into or out of the cell.
d. Only one substance is
transported, while the other
is unaffected
a. Both substances move in the
same direction, both into or
out of the cell.
Which protein complex/es in the ETC
is/are responsible for oxidizing
NADH to NAD+ and FADH2 to FAD,
respectively?
a. Complex II only
b. Complex II and III
c. Complex I and II
d. Complex II and IV
c. Complex I and II
During the electron transport chain,
where is the highest proton
concentration found, which
contributes to the proton motive
force?
a. In the mitochondrial matrix
b. In the cytoplasm
c. In the intermembrane space
d. In the nucleus
c. In the intermembrane space
Which of the following is NOT a
product of glycolysis?
a. Pyruvate
b. ATP
c. NADH
d. Carbon dioxide
d. Carbon dioxide
Pyruvate oxidation results in the
conversion of pyruvate into:
a. Glucose
b. Lactic acid
c. Acetyl-CoA
d. Ethanol
c. Acetyl-CoA
Eukaryotic flagella are composed of
what protein?
a. Dynein
b. Kinesin
c. Tubulin
d. Flagellin
c. Tubulin
What is the first enzyme involved in
pyruvate oxidation that catalyzes the
decarboxylation of pyruvate?
a. Pyruvate dehydrogenase
b. Pyruvate carboxylase
c. Pyruvate kinase
d. Pyruvate decarboxylase
a. Pyruvate dehydrogenase
Which protein is associated with
microfilaments and muscle
contraction?
a. Keratin
b. Actin
c. Tubulin
d. Myosin
b. Actin
Pyruvate oxidation is a critical linker
step between which two major
metabolic pathways in cellular
respiration?
a. Glycolysis and the citric acid
cycle
b. Glycolysis and the electron
transport chain
c. Glycolysis and fermentation
d. Glycolysis and
gluconeogenesis
a. Glycolysis and the citric acid
cycle
How many carbon atoms are present
in each molecule of acetyl CoA?
a. 1
b. 2
c. 3
d. 4
b. 2
What is true about fermentation?
a. It’s a type of anaerobic
respiration
b. It’s a process that produces
large amounts of ATP
c. It’s a metabolic pathway that
does not require oxygen
d. It’s a process that occurs in
the mitochondria
c. It’s a metabolic pathway that
does not require oxygen
What is the main function of
Complex IV in the electron transport
chain?
a. To transfer electrons to
oxygen
b. To generate ATP
c. To convert glucose to
pyruvate
d. To produce NADH
a. To transfer electrons to
oxygen
Which of the following is true about
fermentation?
a. It is anaerobic respiration.
b. It does not utilize the ET
c. Pyruvate serves as the
electron acceptor.
d. It is not part of glycolysis.
c. Pyruvate serves as the
electron acceptor.
In the electron transport chain, the
flow of electrons generates a flow of
protons across a membrane. What is
this flow of protons called?
a. Electron current
b. Proton current
c. Chemiosmotic gradient
d. ATP synthesis
c. Chemiosmotic gradient
What is the function of
desmosomes?
a. Tight junctions that prevent
water leakage between cells
b. Gap junctions that allow
small molecules to pass from
cell to cell
c. Anchoring junctions that
hold cells together during
movement
d. Channels for communication
between adjacent cells
c. Anchoring junctions that
hold cells together during
movement
How many carbons are lost as
carbon dioxide in one turn of the
citric acid cycle (Krebs cycle)?
a. 0 carbons
b. 1 carbon
c. 2 carbons
d. 3 carbons
c. 2 carbons
The coenzyme FAD is first present in
which of the following?
a. Calvin cycle
b. ETC
c. Citric acid cycle
d. Photosynthesis
c. Citric acid cycle
What is the function of ATP synthase
in the electron transport chain
(ETC)?
a. To transport electrons
between complexes
b. To pump protons across the
inner mitochondrial
membrane
c. To convert ADP to ATP using
the proton motive force
d. To reduce oxygen to form
water
c. To convert ADP to ATP using
the proton motive force
What is one role of microtubules in
the cell?
a. Muscle contraction
b. Cell migration
c. Chromosome separation
during cell division
d. Cell structure and stability
c. Chromosome separation
during cell division
Which of the following compounds
can serve as an allosteric regulator
of pyruvate dehydrogenase in cell
respiration?
a. Coenzyme A
b. Citrate
c. NADH
d. Glucose-6-phosphate
c. NADH
How many total molecules of ATP
are produced by substrate-level
phosphorylation for each glucose
that enters glycolysis?
a. 2 ATP
b. 3 ATP
c. 4 ATP
d. 6 ATP
d. 6 ATP
In glycolysis, which enzyme
generates ATP through substrate-level phosphorylation?
a. Hexokinase
b. Phosphofructokinase
c. Pyruvate kinase
d. Aldolase
c. Pyruvate kinase
Short answer:
What is the name of the only component of the ETC that is NOT a protein?
Ubiquinone
Note
Flashcard