Question 1

Specialized channel proteins called connexons occur in

Accepted Answer

A)  the cytoskeleton. 
B)  tight junctions. 
C)  desmosomes. 
D)  plasmodesmata. 
E)  gap junctions. 
A)  the cytoskeleton. 
B)  tight junctions. 
C)  desmosomes. 
D)  plasmodesmata. 
E)  gap junctions.

Question 2

You are studying how the protein transferrin enters cells. When you examine cells that have taken up transferrin, you find it inside clathrin-coated vesicles. Therefore, the most likely mechanism for uptake of transferrin is

Accepted Answer

A)  facilitated diffusion. 
B)  an antiporter. 
C)  receptor-mediated endocytosis. 
D)  gap junctions. 
E)  ion channels. 
A)  facilitated diffusion. 
B)  an antiporter. 
C)  receptor-mediated endocytosis. 
D)  gap junctions. 
E)  ion channels.

Question 3

Which of the following statements about the proteins of the plasma membrane and the proteins of the inner mitochondrial membrane is true?

Accepted Answer

A)  Both membranes have only peripheral proteins. 
B)  Only the mitochondrial membrane has integral proteins. 
C)  Only the mitochondrial membrane has peripheral proteins. 
D)  All of the proteins from both membranes are hydrophilic. 
E)  The two membranes differ in their lipid composition. 
A)  Both membranes have only peripheral proteins. 
B)  Only the mitochondrial membrane has integral proteins. 
C)  Only the mitochondrial membrane has peripheral proteins. 
D)  All of the proteins from both membranes are hydrophilic. 
E)  The two membranes differ in their lipid composition.

Question 4

The sodium-potassium pump of cell membranes is an example of a coupled transport called a(n) _______.

Accepted Answer

The answer of The sodium-potassium pump of cell membranes is...

Question 5

The process of _______ involves coated pits, clathrin, and coated vesicles.

Accepted Answer

receptor-m

Question 6

The coupled transport system by which glucose and sodium ions simultaneously enter intestinal epithelial cells is called _______.

Accepted Answer

The answer of The coupled transport system by which glucose...

Question 7

Which of the following statements regarding osmosis is false?

Accepted Answer

A)  Osmosis refers to the movement of water along a concentration gradient. 
B)  In osmosis, water moves to equalize solute concentrations on either side of the membrane. 
C)  The movement of water across a membrane can affect the turgor pressure of some cells. 
D)  If osmosis occurs across a membrane, then diffusion is not occurring. 
E)  During osmosis water is moving through membrane channels. 
A)  Osmosis refers to the movement of water along a concentration gradient. 
B)  In osmosis, water moves to equalize solute concentrations on either side of the membrane. 
C)  The movement of water across a membrane can affect the turgor pressure of some cells. 
D)  If osmosis occurs across a membrane, then diffusion is not occurring. 
E)  During osmosis water is moving through membrane channels.

Question 8

Most of the lipids composing biological membranes are called _______.

Accepted Answer

The answer of Most of the lipids composing biological membranes...

Question 9

Use the following to answer questions :
The graph below shows the relationship between glucose concentration outside a cell and the rate of glucose diffusion across a cell membrane that has carrier proteins to facilitate diffusion.  
-Which of the following represents saturation of the carrier proteins?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 10

Learning about the formation and operation of plasma membranes may give scientists insights into a disease characterized by plaques and extreme forgetfulness called _______.

Accepted Answer

The answer of Learning about the formation and operation of...

Question 11

Facilitated diffusion

Accepted Answer

A)  is carried out by proteins that exhibit specificity for the molecules they transport. 
B)  does not show saturation of the rate of transport at high concentrations of the molecule transported. 
C)  is carried out by extrinsic membrane proteins. 
D)  can transport a molecule against its concentration gradient. 
E)  is carried out by specific membrane lipids. 
A)  is carried out by proteins that exhibit specificity for the molecules they transport. 
B)  does not show saturation of the rate of transport at high concentrations of the molecule transported. 
C)  is carried out by extrinsic membrane proteins. 
D)  can transport a molecule against its concentration gradient. 
E)  is carried out by specific membrane lipids.

Question 12

The compounds in biological membranes that form a barrier to the movement of hydrophilic materials across the membrane are

Accepted Answer

A)  integral membrane proteins. 
B)  carbohydrates. 
C)  lipids. 
D)  nucleic acids. 
E)  peripheral membrane proteins. 
A)  integral membrane proteins. 
B)  carbohydrates. 
C)  lipids. 
D)  nucleic acids. 
E)  peripheral membrane proteins.

Question 13

The cells that make up a few animals, such as sponges, can be mechanically separated but then will re-form themselves over time. How are the separated cells able to reorganize themselves?

Accepted Answer

The cells in the sponge have the ability

Question 14

Which of the following is not a function of plasma membranes?

Accepted Answer

A)  Conversion of glucose energy to ATP 
B)  Arrangement of enzymes 
C)  Turning off of a specific cell function 
D)  Conduction of nerve impulses 
E)  All of the above are functions of plasma membranes. 
A)  Conversion of glucose energy to ATP 
B)  Arrangement of enzymes 
C)  Turning off of a specific cell function 
D)  Conduction of nerve impulses 
E)  All of the above are functions of plasma membranes.

Question 15

Secondary active transport resembles transport by ion channels in that

Accepted Answer

A)  both types of transport can involve the movement of Na+ across the plasma membrane. 
B)  both types of transport are indirectly linked to the hydrolysis of ATP. 
C)  both can transport molecules against a concentration/electrical gradient. 
D)  the same membrane proteins are used for both types of transport. 
E)  both types of transport resemble facilitated diffusion. 
A)  both types of transport can involve the movement of Na+ across the plasma membrane. 
B)  both types of transport are indirectly linked to the hydrolysis of ATP. 
C)  both can transport molecules against a concentration/electrical gradient. 
D)  the same membrane proteins are used for both types of transport. 
E)  both types of transport resemble facilitated diffusion.

Question 16

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 17

When a hormone molecule binds to a specific protein on the plasma membrane, the protein it binds to is called a

Accepted Answer

A)  ligand. 
B)  clathrin. 
C)  receptor protein. 
D)  hydrophobic protein. 
E)  cell adhesion molecule. 
A)  ligand. 
B)  clathrin. 
C)  receptor protein. 
D)  hydrophobic protein. 
E)  cell adhesion molecule.

Question 18

In facilitated diffusion,

Accepted Answer

A)  molecules may be transported against their concentration gradient. 
B)  specific integral membrane proteins mediate transport. 
C)  the rate of transport is independent of the concentration of the molecule transported. 
D)  ATP is used. 
E)  endocytosis is involved. 
A)  molecules may be transported against their concentration gradient. 
B)  specific integral membrane proteins mediate transport. 
C)  the rate of transport is independent of the concentration of the molecule transported. 
D)  ATP is used. 
E)  endocytosis is involved.

Question 19

In animals, cell recognition

Accepted Answer

A)  involves glycolipids. 
B)  is mediated by the lipid bilayer. 
C)  involves soluble proteins. 
D)  involves proteins in plasma membranes. 
E)  is usually heterotypic. 
A)  involves glycolipids. 
B)  is mediated by the lipid bilayer. 
C)  involves soluble proteins. 
D)  involves proteins in plasma membranes. 
E)  is usually heterotypic.

Question 20

Which of the following statements about cholesterol molecules is true?

Accepted Answer

A)  They help hold a membrane together. 
B)  They transport ions across membranes. 
C)  They attach to carbohydrates. 
D)  They disrupt membrane function. 
E)  They alter the fluidity of the membrane. 
A)  They help hold a membrane together. 
B)  They transport ions across membranes. 
C)  They attach to carbohydrates. 
D)  They disrupt membrane function. 
E)  They alter the fluidity of the membrane.

Exam 6: Cell Membranes

Specialized channel proteins called connexons occur in

You are studying how the protein transferrin enters cells. When you examine cells that have taken up transferrin, you find it inside clathrin-coated vesicles. Therefore, the most likely mechanism for uptake of transferrin is

Which of the following statements about the proteins of the plasma membrane and the proteins of the inner mitochondrial membrane is true?

The sodium-potassium pump of cell membranes is an example of a coupled transport called a(n) _______.

The process of _______ involves coated pits, clathrin, and coated vesicles.

The coupled transport system by which glucose and sodium ions simultaneously enter intestinal epithelial cells is called _______.

Which of the following statements regarding osmosis is false?

Most of the lipids composing biological membranes are called _______.

Learning about the formation and operation of plasma membranes may give scientists insights into a disease characterized by plaques and extreme forgetfulness called _______.

Facilitated diffusion

The compounds in biological membranes that form a barrier to the movement of hydrophilic materials across the membrane are

The cells that make up a few animals, such as sponges, can be mechanically separated but then will re-form themselves over time. How are the separated cells able to reorganize themselves?

Which of the following is not a function of plasma membranes?

Secondary active transport resembles transport by ion channels in that

Receptor-mediated endocytosis is the mechanism for transport of

When a hormone molecule binds to a specific protein on the plasma membrane, the protein it binds to is called a

In facilitated diffusion,

In animals, cell recognition

Which of the following statements about cholesterol molecules is true?

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 Signaling and Communication

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

Recombinent Dna and Biotechnology

Differential Gene Expression in Development

Development and Evolutionary Change

Evidence and Mechanisms of Evolution

Reconstructing and Using Phylogenies

Species and Their Formation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria and Archaea: the Prokaryotic Domains

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

Fungi: Recyclers, Pathogens, Parasites, and Plant Partners

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 and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Function

Musculoskeletal Systems

Gas Exchange in Animals

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen

Animal Behavior

Ecology and the Distribution of Life

Population Ecology

Species Interaction and Coevolution

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