Test Bank
to accompany
Life: The Science of Biology, Eleventh Edition
Sadava • Hillis • Heller • Hacker
Chapter 6: Cell Membranes
TEST BANK QUESTIONS
Multiple Choice
1. The membrane components that enable a biological membrane to have fluidity are
a. integral membrane proteins.
b. carbohydrates.
c. oligosaccharides.
d. peripheral membrane proteins.
e. lipids.
Answer: e
Learning Outcome: 6.1.1.a Describe the general structure of a biological membrane
according to the fluid mosaic model.
Bloom’s Level: 1. Remembering
2. The compounds in a biological membrane that form a barrier to the movement of
hydrophilic materials across the membrane are
a. integral membrane proteins.
b. carbohydrates.
c. lipids.
d. nucleic acids.
e. peripheral membrane proteins.
Answer: c
Learning Outcome: 6.1.1.a Describe the general structure of a biological membrane
according to the fluid mosaic model.
Bloom’s Level: 2. Understanding
3. In a biological membrane, the phospholipids are arranged in a _______, with the
_______.
a. bilayer; fatty acid tails pointing toward each other
b. bilayer; fatty acid tails facing outward
c. single layer; fatty acid tails facing the interior of the cell
d. single layer; phosphorus-containing region facing the interior of the cell
e. bilayer; phosphorus groups in the interior of the membrane
Answer: a
Learning Outcome: 6.1.2.a Explain how the hydrophobic and hydrophilic regions of
,phospholipids are involved in membrane formation.
Bloom’s Level: 2. Understanding
4. Refer to the figure below.
Which statement about the lipid bilayer shown in the figure is false?
a. The area labeled A contains hydrophilic portions of fatty acids.
b. The area labeled A contains polar groups that can interact with water.
c. The area labeled B contains hydrophobic regions of fatty acids.
d. The area labeled B allows for the movement of charged particles.
e. The area labeled B allows for the diffusion of lipid-soluble particles.
Answer: d
Learning Outcome: 6.1.2.a Explain how the hydrophobic and hydrophilic regions of
phospholipids are involved in membrane formation.
Bloom’s Level: 2. Understanding
5. Which observation can be used as evidence that the cell membrane has a fluid nature?
a. In the laboratory, two cells from different species can be fused together to make one
large cell.
b. Images obtained using freeze-fracture electron microscopy reveal that the membrane
contains embedded proteins.
c. Chemical analysis reveals that cell membranes contain phospholipids, proteins, and
cholesterol as major components.
d. Analysis of the amino acids present in protein regions embedded in cell membranes
show that they mainly have hydrophobic side chains.
e. The cholesterol content in cell membranes varies depending on cell type, and it is
generally higher than in organelle membranes.
Answer: a
Learning Outcome: 6.1.3.a Describe a property of a cell membrane that results from its
fluid nature.
Bloom’s Level: 5. Evaluating
6. One student mentioned to another that the fluidity of a cell membrane can be changed
by changing the membrane’s lipid composition. The second student expressed doubt
about this claim. What evidence could the first student find in a research journal to
support his claim?
a. A comparison of lipid compositions of membranes in different cells within the same
organism
b. An analysis of the change in fatty acid compositions of liver cell membranes in
juvenile fish as they mature into adults
c. Results from cell fusion experiments between the same two cells that measure
diffusion rates of different membrane proteins
d. Measurement of diffusion rates of the same protein in cell membranes containing
different percentages of saturated and unsaturated fatty acids
,e. An analysis of the saturated and unsaturated fatty acid content in membranes of skin
cells from a single population of cane toads
Answer: d
Learning Outcome: 6.1.4.a Cite experimental evidence to support the claim that
composition and temperature affect a membrane’s fluidity.
Bloom’s Level: 5. Evaluating
7. Experimental results from five different studies on cell membranes are given. Which
results could be used as evidence to support the claim that temperature affects a
membrane’s fluidity?
a. Results from freeze-fracture imaging of cell membranes isolated from blood cells of
Arctic and desert rabbits
b. A comparison of diffusion rates of different membrane proteins at 37°C in the cell
membranes of liver cells from mice
c. A chemical analysis of the saturated and unsaturated fatty acid content in membranes
of intestinal cells from a single population of tropical frogs
d. A comparison of lipid compositions of membranes in different cells within the same
organism
e. An analysis of the change in fatty acid compositions of liver cell membranes in a fish
species before and after they migrate from warm to cold waters
Answer: e
Learning Outcome: 6.1.4.a Cite experimental evidence to support the claim that
composition and temperature affect a membrane’s fluidity.
Bloom’s Level: 5. Evaluating
8. The plasma membrane of the bacterium Pseudomonas syringae is able to remain fluid
when it is extremely cold. The bacterium most likely accomplishes this by
a. increasing the number of cholesterol molecules present.
b. closing protein channels.
c. decreasing the number of hydrophobic proteins present.
d. replacing saturated fatty acids with unsaturated fatty acids.
e. using fatty acids with longer tails.
Answer: d
Learning Outcome: 6.1.4.b Predict how changes in composition or temperature will affect
properties of a membrane.
Bloom’s Level: 3. Applying
9. How do the cell membranes of a hibernating animal change in colder temperatures?
a. Cholesterol content is increased.
b. Saturated fatty acids are more tightly packed.
c. Integral membrane proteins increase in number.
d. Unsaturated fatty acids make up more of the lipid composition.
e. Fatty acids with longer tails increase in number.
Answer: d
Learning Outcome: 6.1.4.b Predict how changes in composition or temperature will affect
properties of a membrane.
Bloom’s Level: 3. Applying
, 10. Refer to the table below.
According to the data presented in the table, biological membranes differ in composition
because of differences in
a. gene expression.
b. anatomical location.
c. lipid arrangement.
d. biological origin.
e. biological function.
Answer: e
Learning Outcome: 6.1.4.c Analyze experimental results to compare membrane
compositions and fluidity across species.
Bloom’s Level: 4. Analyzing
11. Which membrane protein type would likely be removed most easily from a cell
membrane in a laboratory experiment?
a. Integral proteins
b. Channel proteins
c. Peripheral proteins
d. Transmembrane proteins
e. Gated channels
Answer: c
Learning Outcome: 6.1.5.a Differentiate between integral proteins and peripheral
proteins.
Bloom’s Level: 5. Evaluating
12. If the hydrophilic side chains of a transmembrane protein were removed, the protein
would most likely
a. remain within the phospholipid bilayer.
b. extend farther into the cytoplasm.
c. protrude into the extracellular space.
d. remain anchored to the cytoskeleton.
e. become a peripheral protein.
Answer: a
Learning Outcome: 6.1.5.a Differentiate between integral proteins and peripheral
proteins.
Bloom’s Level: 3. Applying
13. Membrane proteins are asymmetrically distributed according to the function of the
membrane and its lipid composition. Which statement about peripheral membrane
proteins is true?
a. They do not contain any hydrophilic regions.
b. They are embedded in the phospholipid bilayer.
c. They are able to move freely within the plasma membrane.
to accompany
Life: The Science of Biology, Eleventh Edition
Sadava • Hillis • Heller • Hacker
Chapter 6: Cell Membranes
TEST BANK QUESTIONS
Multiple Choice
1. The membrane components that enable a biological membrane to have fluidity are
a. integral membrane proteins.
b. carbohydrates.
c. oligosaccharides.
d. peripheral membrane proteins.
e. lipids.
Answer: e
Learning Outcome: 6.1.1.a Describe the general structure of a biological membrane
according to the fluid mosaic model.
Bloom’s Level: 1. Remembering
2. The compounds in a biological membrane that form a barrier to the movement of
hydrophilic materials across the membrane are
a. integral membrane proteins.
b. carbohydrates.
c. lipids.
d. nucleic acids.
e. peripheral membrane proteins.
Answer: c
Learning Outcome: 6.1.1.a Describe the general structure of a biological membrane
according to the fluid mosaic model.
Bloom’s Level: 2. Understanding
3. In a biological membrane, the phospholipids are arranged in a _______, with the
_______.
a. bilayer; fatty acid tails pointing toward each other
b. bilayer; fatty acid tails facing outward
c. single layer; fatty acid tails facing the interior of the cell
d. single layer; phosphorus-containing region facing the interior of the cell
e. bilayer; phosphorus groups in the interior of the membrane
Answer: a
Learning Outcome: 6.1.2.a Explain how the hydrophobic and hydrophilic regions of
,phospholipids are involved in membrane formation.
Bloom’s Level: 2. Understanding
4. Refer to the figure below.
Which statement about the lipid bilayer shown in the figure is false?
a. The area labeled A contains hydrophilic portions of fatty acids.
b. The area labeled A contains polar groups that can interact with water.
c. The area labeled B contains hydrophobic regions of fatty acids.
d. The area labeled B allows for the movement of charged particles.
e. The area labeled B allows for the diffusion of lipid-soluble particles.
Answer: d
Learning Outcome: 6.1.2.a Explain how the hydrophobic and hydrophilic regions of
phospholipids are involved in membrane formation.
Bloom’s Level: 2. Understanding
5. Which observation can be used as evidence that the cell membrane has a fluid nature?
a. In the laboratory, two cells from different species can be fused together to make one
large cell.
b. Images obtained using freeze-fracture electron microscopy reveal that the membrane
contains embedded proteins.
c. Chemical analysis reveals that cell membranes contain phospholipids, proteins, and
cholesterol as major components.
d. Analysis of the amino acids present in protein regions embedded in cell membranes
show that they mainly have hydrophobic side chains.
e. The cholesterol content in cell membranes varies depending on cell type, and it is
generally higher than in organelle membranes.
Answer: a
Learning Outcome: 6.1.3.a Describe a property of a cell membrane that results from its
fluid nature.
Bloom’s Level: 5. Evaluating
6. One student mentioned to another that the fluidity of a cell membrane can be changed
by changing the membrane’s lipid composition. The second student expressed doubt
about this claim. What evidence could the first student find in a research journal to
support his claim?
a. A comparison of lipid compositions of membranes in different cells within the same
organism
b. An analysis of the change in fatty acid compositions of liver cell membranes in
juvenile fish as they mature into adults
c. Results from cell fusion experiments between the same two cells that measure
diffusion rates of different membrane proteins
d. Measurement of diffusion rates of the same protein in cell membranes containing
different percentages of saturated and unsaturated fatty acids
,e. An analysis of the saturated and unsaturated fatty acid content in membranes of skin
cells from a single population of cane toads
Answer: d
Learning Outcome: 6.1.4.a Cite experimental evidence to support the claim that
composition and temperature affect a membrane’s fluidity.
Bloom’s Level: 5. Evaluating
7. Experimental results from five different studies on cell membranes are given. Which
results could be used as evidence to support the claim that temperature affects a
membrane’s fluidity?
a. Results from freeze-fracture imaging of cell membranes isolated from blood cells of
Arctic and desert rabbits
b. A comparison of diffusion rates of different membrane proteins at 37°C in the cell
membranes of liver cells from mice
c. A chemical analysis of the saturated and unsaturated fatty acid content in membranes
of intestinal cells from a single population of tropical frogs
d. A comparison of lipid compositions of membranes in different cells within the same
organism
e. An analysis of the change in fatty acid compositions of liver cell membranes in a fish
species before and after they migrate from warm to cold waters
Answer: e
Learning Outcome: 6.1.4.a Cite experimental evidence to support the claim that
composition and temperature affect a membrane’s fluidity.
Bloom’s Level: 5. Evaluating
8. The plasma membrane of the bacterium Pseudomonas syringae is able to remain fluid
when it is extremely cold. The bacterium most likely accomplishes this by
a. increasing the number of cholesterol molecules present.
b. closing protein channels.
c. decreasing the number of hydrophobic proteins present.
d. replacing saturated fatty acids with unsaturated fatty acids.
e. using fatty acids with longer tails.
Answer: d
Learning Outcome: 6.1.4.b Predict how changes in composition or temperature will affect
properties of a membrane.
Bloom’s Level: 3. Applying
9. How do the cell membranes of a hibernating animal change in colder temperatures?
a. Cholesterol content is increased.
b. Saturated fatty acids are more tightly packed.
c. Integral membrane proteins increase in number.
d. Unsaturated fatty acids make up more of the lipid composition.
e. Fatty acids with longer tails increase in number.
Answer: d
Learning Outcome: 6.1.4.b Predict how changes in composition or temperature will affect
properties of a membrane.
Bloom’s Level: 3. Applying
, 10. Refer to the table below.
According to the data presented in the table, biological membranes differ in composition
because of differences in
a. gene expression.
b. anatomical location.
c. lipid arrangement.
d. biological origin.
e. biological function.
Answer: e
Learning Outcome: 6.1.4.c Analyze experimental results to compare membrane
compositions and fluidity across species.
Bloom’s Level: 4. Analyzing
11. Which membrane protein type would likely be removed most easily from a cell
membrane in a laboratory experiment?
a. Integral proteins
b. Channel proteins
c. Peripheral proteins
d. Transmembrane proteins
e. Gated channels
Answer: c
Learning Outcome: 6.1.5.a Differentiate between integral proteins and peripheral
proteins.
Bloom’s Level: 5. Evaluating
12. If the hydrophilic side chains of a transmembrane protein were removed, the protein
would most likely
a. remain within the phospholipid bilayer.
b. extend farther into the cytoplasm.
c. protrude into the extracellular space.
d. remain anchored to the cytoskeleton.
e. become a peripheral protein.
Answer: a
Learning Outcome: 6.1.5.a Differentiate between integral proteins and peripheral
proteins.
Bloom’s Level: 3. Applying
13. Membrane proteins are asymmetrically distributed according to the function of the
membrane and its lipid composition. Which statement about peripheral membrane
proteins is true?
a. They do not contain any hydrophilic regions.
b. They are embedded in the phospholipid bilayer.
c. They are able to move freely within the plasma membrane.
