Question 1

Transporters that move two substances at once are known as

Accepted Answer

A)  uniporters. 
B)  facilitated transporters. 
C)  secondary active transporters. 
D)  coupled transporters. 
E)  directional transporters. 
A)  uniporters. 
B)  facilitated transporters. 
C)  secondary active transporters. 
D)  coupled transporters. 
E)  directional transporters.

Question 2

All of the following affect the rate of diffusion of a substance except

Accepted Answer

A)  the temperature of the solution. 
B)  the concentration gradient of the diffusing particles. 
C)  the density of the solution. 
D)  the presence of other solutes in the solution. 
E)  the size of the diffusing particles. 
A)  the temperature of the solution. 
B)  the concentration gradient of the diffusing particles. 
C)  the density of the solution. 
D)  the presence of other solutes in the solution. 
E)  the size of the diffusing particles.

Question 3

Osmosis is a specific form of

Accepted Answer

A)  active transport. 
B)  pinocytosis. 
C)  diffusion. 
D)  secondary active transport. 
E)  movement of water by carrier proteins. 
A)  active transport. 
B)  pinocytosis. 
C)  diffusion. 
D)  secondary active transport. 
E)  movement of water by carrier proteins.

Question 4

Lactose is transported via secondary active transport into bacterial cells.Which of the following would be absent from a diagram illustrating the mechanism of this transport system?

Accepted Answer

A)  The direct use of ATP to transport lactose 
B)  Coupling of lactose transport to transport of another substance 
C)  The formation of a concentration gradient 
D)  Diffusion of a substance in the same direction as its concentration gradient 
E)  The movement of lactose against its concentration gradient 
A)  The direct use of ATP to transport lactose 
B)  Coupling of lactose transport to transport of another substance 
C)  The formation of a concentration gradient 
D)  Diffusion of a substance in the same direction as its concentration gradient 
E)  The movement of lactose against its concentration gradient

Question 5

Refer to the table below showing data collected from analyses of the phospholipid compositions of cell membranes isolated from four different species.   Use the data to rank the four species according to the temperature conditions characteristic of their native environments.The predicted ranking from coldest to warmest is _______.

Accepted Answer

The answer of Refer to the table below showing data...

Question 6

A biologist is interested in identifying pairs of molecular structures responsible for adhesion between bovine (cow) intestinal cells.Which pairs of structures should the biologist include as possibilities during his search?

Accepted Answer

A)  Lipid-carbohydrate, carbohydrate-carbohydrate, lipid-lipid 
B)  Protein-lipid, lipid-lipid, protein-protein 
C)  Carbohydrate-carbohydrate, protein-carbohydrate, protein-protein 
D)  Lipid-carbohydrate, protein-lipid, carbohydrate-protein 
E)  Carbohydrate-carbohydrate, protein-protein, lipid-lipid 
A)  Lipid-carbohydrate, carbohydrate-carbohydrate, lipid-lipid 
B)  Protein-lipid, lipid-lipid, protein-protein 
C)  Carbohydrate-carbohydrate, protein-carbohydrate, protein-protein 
D)  Lipid-carbohydrate, protein-lipid, carbohydrate-protein 
E)  Carbohydrate-carbohydrate, protein-protein, lipid-lipid

Question 7

A specific ligand in receptor-mediated endocytosis is most likely

Accepted Answer

A)  a dissolved solute that enters the membrane. 
B)  clathrin-coated pits on the membrane. 
C)  a bacterium capable of being phagocytized. 
D)  free cholesterol that is unpackaged. 
E)  a specific macromolecule. 
A)  a dissolved solute that enters the membrane. 
B)  clathrin-coated pits on the membrane. 
C)  a bacterium capable of being phagocytized. 
D)  free cholesterol that is unpackaged. 
E)  a specific macromolecule.

Question 8

Refer to the table below.   A hormone called epidermal growth factor is taken up by certain cells in mammals through receptor mediated endocytosis.Once inside cells, this hormone stimulates cell growth and differentiation.Female mice known to carry a mutation in the epidermal growth factor receptor were observed to have the characteristics summarized in the table.This mutation likely affects mammals in general.Of the types listed, which mammalian cells are likely affected by this mutation?

Accepted Answer

A)  Mammary glands 
B)  Ovaries 
C)  Heart 
D)  Kidneys 
E)  Lungs 
A)  Mammary glands 
B)  Ovaries 
C)  Heart 
D)  Kidneys 
E)  Lungs

Question 9

Receptor-mediated endocytosis is the mechanism for transport of

Accepted Answer

A)  clathrin. 
B)  all macromolecules. 
C)  ions. 
D)  cholesterol. 
E)  integral membrane proteins. 
A)  clathrin. 
B)  all macromolecules. 
C)  ions. 
D)  cholesterol. 
E)  integral membrane proteins.

Question 10

Which factor does not affect the rate of diffusion of a substance?

Accepted Answer

A)  Temperature of the solution 
B)  Concentration gradient 
C)  Density of the solution 
D)  Presence of other solutes in the solution 
E)  Molecular diameter of the diffusing material 
A)  Temperature of the solution 
B)  Concentration gradient 
C)  Density of the solution 
D)  Presence of other solutes in the solution 
E)  Molecular diameter of the diffusing material

Question 11

If a cell were bathed in an extracellular solution high in Na+, what type of ion movement would maintain the proper balance of Na+ ions between the inside and the outside of the cell?

Accepted Answer

A)  Active transport of Na+ against its concentration gradient 
B)  Facilitated diffusion of Na+ through ion channels 
C)  Secondary active transport of K+ 
D)  Simple diffusion of Na+ 
E)  Simple diffusion of K+ 
A)  Active transport of Na+ against its concentration gradient 
B)  Facilitated diffusion of Na+ through ion channels 
C)  Secondary active transport of K+ 
D)  Simple diffusion of Na+ 
E)  Simple diffusion of K+

Question 12

Refer to the figure below.   The figure shows a type of facilitated diffusion that involves a membrane protein called a(n) _______ protein.This example is similar to all other examples of facilitated diffusion in that it does not require the input of energy to move substances across a biological membrane.

Accepted Answer

The answer of Refer to the figure below.  ...

Question 13

The directions of ions as they move into and out of the cell are determined by the

Accepted Answer

A)  ability of the ions to let go of their water. 
B)  ion concentration gradient. 
C)  number of channel proteins present. 
D)  size and charge of the ions. 
E)  presence of specific stimuli to open gated channel proteins. 
A)  ability of the ions to let go of their water. 
B)  ion concentration gradient. 
C)  number of channel proteins present. 
D)  size and charge of the ions. 
E)  presence of specific stimuli to open gated channel proteins.

Question 14

Refer to the figure below.   Which statement regarding the sequence of events shown in the figure is true?

Accepted Answer

A)  The cells in condition B have less turgor pressure than the cells in condition A. 
B)  The cells in condition A have been placed in a hypotonic solution. 
C)  The cells in condition C have been placed in a hypertonic solution. 
D)  The cells in condition C have been placed in an isotonic solution. 
E)  The cells in condition C have greater turgor pressure than the cells in condition B. 
A)  The cells in condition B have less turgor pressure than the cells in condition A. 
B)  The cells in condition A have been placed in a hypotonic solution. 
C)  The cells in condition C have been placed in a hypertonic solution. 
D)  The cells in condition C have been placed in an isotonic solution. 
E)  The cells in condition C have greater turgor pressure than the cells in condition B.

Question 15

The process of random movement of molecules toward a state of equilibrium is called _______.

Accepted Answer

The answer of The process of random movement of molecules...

Question 16

A student claims that both freeze-fracturing techniques and cell fusion experiments provided evidence that supported the fluid mosaic model used to describe the cell membrane.Which statement best evaluates this student's claim?

Accepted Answer

A)  The claim is accurate because freeze-fracturing techniques revealed protein movement within a membrane, while cell fusion experiments showed how proteins were embedded in the lipid bilayer. 
B)  The claim is accurate because freeze-fracturing techniques showed how proteins were embedded in the lipid bilayer, while cell fusion experiments revealed protein movement within a membrane. 
C)  The claim is inaccurate because freeze-fracturing techniques did not show how proteins or lipids could move about within a membrane as cell fusion experiments did. 
D)  The claim is inaccurate because cell fusion experiments did not reveal the distribution of proteins within the lipid bilayer as freeze-fracturing techniques did. 
E)  The claim is inaccurate because the fluid mosaic model is supported by evidence obtained from experiments other than those using freeze-fracturing or cell fusion techniques. 
A)  The claim is accurate because freeze-fracturing techniques revealed protein movement within a membrane, while cell fusion experiments showed how proteins were embedded in the lipid bilayer. 
B)  The claim is accurate because freeze-fracturing techniques showed how proteins were embedded in the lipid bilayer, while cell fusion experiments revealed protein movement within a membrane. 
C)  The claim is inaccurate because freeze-fracturing techniques did not show how proteins or lipids could move about within a membrane as cell fusion experiments did. 
D)  The claim is inaccurate because cell fusion experiments did not reveal the distribution of proteins within the lipid bilayer as freeze-fracturing techniques did. 
E)  The claim is inaccurate because the fluid mosaic model is supported by evidence obtained from experiments other than those using freeze-fracturing or cell fusion techniques.

Question 17

Which observation can be used as evidence that the cell membrane has a fluid nature?

Accepted Answer

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. 
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.

Question 18

Which statement about the process of diffusion is true?

Accepted Answer

A)  The concentration gradient of a solute depends on the size of the molecule. 
B)  Equilibrium in a solution is the end point of diffusion. 
C)  The net movement of particles depends on the temperature of the solution. 
D)  Diffusion is most efficient over long distances. 
E)  Diffusion can reduce selective permeability of a membrane. 
A)  The concentration gradient of a solute depends on the size of the molecule. 
B)  Equilibrium in a solution is the end point of diffusion. 
C)  The net movement of particles depends on the temperature of the solution. 
D)  Diffusion is most efficient over long distances. 
E)  Diffusion can reduce selective permeability of a membrane.

Question 19

Which membrane protein type would likely be removed most easily from a cell membrane in a laboratory experiment?

Accepted Answer

A)  Integral proteins 
B)  Channel proteins 
C)  Peripheral proteins 
D)  Transmembrane proteins 
E)  Gated channels 
A)  Integral proteins 
B)  Channel proteins 
C)  Peripheral proteins 
D)  Transmembrane proteins 
E)  Gated channels

Question 20

Ion channels are formed by a particular kind of membrane protein that allows the passage of a specific ion under certain conditions.This type of protein is most likely a(n)

Accepted Answer

A)  peripheral protein with additional hydrophobic domains. 
B)  integral protein with a transmembrane domain. 
C)  phospholipid with hydrophilic domains. 
D)  enzyme with an asymmetrical arrangement on either side of the plasma membrane. 
E)  membrane protein that is able to move freely within the phospholipid bilayer. 
A)  peripheral protein with additional hydrophobic domains. 
B)  integral protein with a transmembrane domain. 
C)  phospholipid with hydrophilic domains. 
D)  enzyme with an asymmetrical arrangement on either side of the plasma membrane. 
E)  membrane protein that is able to move freely within the phospholipid bilayer.

Exam 6: Cell Membranes

Transporters that move two substances at once are known as

All of the following affect the rate of diffusion of a substance except

Osmosis is a specific form of

Lactose is transported via secondary active transport into bacterial cells.Which of the following would be absent from a diagram illustrating the mechanism of this transport system?

A biologist is interested in identifying pairs of molecular structures responsible for adhesion between bovine (cow) intestinal cells.Which pairs of structures should the biologist include as possibilities during his search?

A specific ligand in receptor-mediated endocytosis is most likely

Receptor-mediated endocytosis is the mechanism for transport of

Which factor does not affect the rate of diffusion of a substance?

If a cell were bathed in an extracellular solution high in Na+, what type of ion movement would maintain the proper balance of Na+ ions between the inside and the outside of the cell?

The directions of ions as they move into and out of the cell are determined by the

Refer to the figure below. Which statement regarding the sequence of events shown in the figure is true?

The process of random movement of molecules toward a state of equilibrium is called _______.

A student claims that both freeze-fracturing techniques and cell fusion experiments provided evidence that supported the fluid mosaic model used to describe the cell membrane.Which statement best evaluates this student's claim?

Which observation can be used as evidence that the cell membrane has a fluid nature?

Which statement about the process of diffusion is true?

Which membrane protein type would likely be removed most easily from a cell membrane in a laboratory experiment?

Ion channels are formed by a particular kind of membrane protein that allows the passage of a specific ion under certain conditions.This type of protein is most likely a(n)

Studying Life

Small Molecules and the Chemistry of Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Communication and Multicellularity

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

Populations

Species Interactions

Communities

Ecosystems

A Changing Biosphere

Filters

If a cell were bathed in an extracellular solution high in Na⁺, what type of ion movement would maintain the proper balance of Na⁺ ions between the inside and the outside of the cell?