Question 1

To say that a cell is ʺselectively permeableʺ means

Accepted Answer

A)  sometimes water passes through, and sometimes it canʹt. 
B)  it is permeable to different substances than other cells. 
C)  only certain molecules can pass through. 
D)  it has different-sized perforations in the membrane. 
E)  permeability depends on gradient differences. 
A)  sometimes water passes through, and sometimes it canʹt. 
B)  it is permeable to different substances than other cells. 
C)  only certain molecules can pass through. 
D)  it has different-sized perforations in the membrane. 
E)  permeability depends on gradient differences.

Question 2

Imagine an artificial cell made with a selectively permeable membrane that allows water to pass through but does not allow sugar to pass. If the artificial cell contains a 1% sugar solution and then you place the cell in a 2% sugar solution, what happens?

Accepted Answer

A)  Sugar diffuses in and water diffuses out until equilibrium is reached. 
B)  Water enters the cell because the solution is hypotonic to the cell. 
C)  There is no movement of water. 
D)  Water leaves the cell because the solution is hypertonic to the cell. 
A)  Sugar diffuses in and water diffuses out until equilibrium is reached. 
B)  Water enters the cell because the solution is hypotonic to the cell. 
C)  There is no movement of water. 
D)  Water leaves the cell because the solution is hypertonic to the cell.

Question 3

What structure in the membrane causes plasma membranes to resist freezing?

Accepted Answer

A)  Cholesterol 
B)  Unsaturated fatty acid tails 
C)  Nonpolar heads of the phospholipids 
D)  Saturated fatty acid tails 
E)  Channel proteins 
A)  Cholesterol 
B)  Unsaturated fatty acid tails 
C)  Nonpolar heads of the phospholipids 
D)  Saturated fatty acid tails 
E)  Channel proteins

Question 4

Which of the following occurs as an enzyme produced by a cell is secreted from the cell?

Accepted Answer

A)  Pinocytosis 
B)  Receptor-mediated endocytosis 
C)  Endocytosis 
D)  Exocytosis 
E)  Phagocytosis 
A)  Pinocytosis 
B)  Receptor-mediated endocytosis 
C)  Endocytosis 
D)  Exocytosis 
E)  Phagocytosis

Question 5

Phospholipids spontaneously form a bilayer in an aqueous solution. Why do the heads of the phospholipids point out and the tails point toward one another?

Accepted Answer

A)  The tails are repelled by the aqueous environment, and the heads will directly interact with the aqueous solution. 
B)  The tails are nonpolar and form hydrogen bonds with one another. 
C)  The heads are repelled by the water inside and outside the cell. 
A)  The tails are repelled by the aqueous environment, and the heads will directly interact with the aqueous solution. 
B)  The tails are nonpolar and form hydrogen bonds with one another. 
C)  The heads are repelled by the water inside and outside the cell.

Question 6

Compare and contrast the intercellular junctions that allow communication between plant and animal cells.

Accepted Answer

Gap junctions in animal cells

Question 7

A freshwater protozoan, such as Paramecium, tends to__________ because it lives in a__________ environment.

Accepted Answer

A)  gain water; isotonic 
B)  lose water; hypertonic 
C)  lose water; hypotonic 
D)  gain water; hypertonic 
E)  gain water; hypotonic 
A)  gain water; isotonic 
B)  lose water; hypertonic 
C)  lose water; hypotonic 
D)  gain water; hypertonic 
E)  gain water; hypotonic

Question 8

In general, which of the following is (are) largely responsible for moving substances across the plasma membrane, communicating with other cells, and identifying the cell?

Accepted Answer

A)  Cytoskeleton 
B)  Proteins 
C)  Nucleic acids 
D)  Carbohydrates 
E)  Phospholipids 
A)  Cytoskeleton 
B)  Proteins 
C)  Nucleic acids 
D)  Carbohydrates 
E)  Phospholipids

Question 9

Which of the following types of membrane proteins are responsible for conveying external messages such as those sent by a hormone signal?

Accepted Answer

A)  Receptor proteins 
B)  Recognition proteins 
C)  Transport proteins 
D)  Enzymes 
E)  Connection proteins 
A)  Receptor proteins 
B)  Recognition proteins 
C)  Transport proteins 
D)  Enzymes 
E)  Connection proteins

Question 10

Cells use exocytosis to

Accepted Answer

A)  move away from danger. 
B)  ingest nutrients. 
C)  pump hydrogen molecules across the membrane. 
D)  release substances from the cell. 
E)  create new cells. 
A)  move away from danger. 
B)  ingest nutrients. 
C)  pump hydrogen molecules across the membrane. 
D)  release substances from the cell. 
E)  create new cells.

Question 11

Which of the following types of membrane proteins are responsible for facilitated diffusion?

Accepted Answer

A)  Connection proteins 
B)  Receptor proteins 
C)  Enzymes 
D)  Transport proteins 
E)  Recognition proteins 
A)  Connection proteins 
B)  Receptor proteins 
C)  Enzymes 
D)  Transport proteins 
E)  Recognition proteins

Question 12

Which of the following groups includes carrier and channel proteins?

Accepted Answer

A)  Transport proteins 
B)  Receptor proteins 
C)  Connection proteins 
D)  Recognition proteins 
A)  Transport proteins 
B)  Receptor proteins 
C)  Connection proteins 
D)  Recognition proteins

Question 13

The__________ portion of the cell membrane is responsible for the isolating function of the membrane, whereas the__________ portion regulates exchange and communication with the environment.

Accepted Answer

A)  carbohydrate; lipid 
B)  lipid; protein 
C)  cholesterol; lipid 
D)  nucleic acid; lipid 
E)  protein; cholesterol 
A)  carbohydrate; lipid 
B)  lipid; protein 
C)  cholesterol; lipid 
D)  nucleic acid; lipid 
E)  protein; cholesterol

Question 14

Why does the cell perform endocytosis in addition to active and passive transport?

Accepted Answer

Endocytosis is required for th

Question 15

How does the cell membrane act as a ʺgatekeeperʺ for the cell?

Accepted Answer

It separates the internal and

Question 16

The slowest rate of diffusion of dye particles in water will occur at

Accepted Answer

A)  20°C. 
B)  30°C. 
C)  60°C. 
D)  10°C. 
A)  20°C. 
B)  30°C. 
C)  60°C. 
D)  10°C.

Question 17

The cells of the bladder are joined to one another by __________that prevent substances from passing between the cells of this tissue.

Accepted Answer

The answer of The cells of the bladder are joined...

Question 18

Glucose is a six-carbon sugar that diffuses slowly through artificial phospholipid bilayers. The cells lining the small intestine, however, rapidly move large quantities of glucose from the glucose-rich food into their glucose-poor cytoplasm. Given this information, which transport mechanism is most probably functioning in the intestinal cells?

Accepted Answer

A)  Exocytosis 
B)  Facilitated diffusion 
C)  Aquaporin transport 
D)  Simple diffusion 
E)  Osmosis 
A)  Exocytosis 
B)  Facilitated diffusion 
C)  Aquaporin transport 
D)  Simple diffusion 
E)  Osmosis

Question 19

What happens when diffusion moves molecules across the plasma membrane?

Accepted Answer

A)  Most molecules are capable of crossing the phospholipid bilayer at any location and at basically the same rate. 
B)  Energy input is required to transport molecules. 
C)  The rate of diffusion cannot be influenced by the cell. 
D)  The cell gains needed materials and gets rid of excess materials very quickly. 
E)  The process is relatively slow and is driven by concentration gradients. 
A)  Most molecules are capable of crossing the phospholipid bilayer at any location and at basically the same rate. 
B)  Energy input is required to transport molecules. 
C)  The rate of diffusion cannot be influenced by the cell. 
D)  The cell gains needed materials and gets rid of excess materials very quickly. 
E)  The process is relatively slow and is driven by concentration gradients.

Question 20

Suppose you have two glucose solutions separated by a selectively permeable membrane. If there is a concentration gradient of glucose across the membrane, then the solutions cannot be relative to each other.

Accepted Answer

A)  isotonic 
B)  hypertonic 
C)  hypotonic 
A)  isotonic 
B)  hypertonic 
C)  hypotonic

Exam 5: Cell Membrane Structure and Function

To say that a cell is ʺselectively permeableʺ means

Imagine an artificial cell made with a selectively permeable membrane that allows water to pass through but does not allow sugar to pass. If the artificial cell contains a 1% sugar solution and then you place the cell in a 2% sugar solution, what happens?

What structure in the membrane causes plasma membranes to resist freezing?

Which of the following occurs as an enzyme produced by a cell is secreted from the cell?

Phospholipids spontaneously form a bilayer in an aqueous solution. Why do the heads of the phospholipids point out and the tails point toward one another?

Compare and contrast the intercellular junctions that allow communication between plant and animal cells.

A freshwater protozoan, such as Paramecium, tends to__________ because it lives in a__________ environment.

In general, which of the following is (are) largely responsible for moving substances across the plasma membrane, communicating with other cells, and identifying the cell?

Which of the following types of membrane proteins are responsible for conveying external messages such as those sent by a hormone signal?

Cells use exocytosis to

Which of the following types of membrane proteins are responsible for facilitated diffusion?

Which of the following groups includes carrier and channel proteins?

The__________ portion of the cell membrane is responsible for the isolating function of the membrane, whereas the__________ portion regulates exchange and communication with the environment.

Why does the cell perform endocytosis in addition to active and passive transport?

How does the cell membrane act as a ʺgatekeeperʺ for the cell?

The slowest rate of diffusion of dye particles in water will occur at

The cells of the bladder are joined to one another by __________that prevent substances from passing between the cells of this tissue.

What happens when diffusion moves molecules across the plasma membrane?

Suppose you have two glucose solutions separated by a selectively permeable membrane. If there is a concentration gradient of glucose across the membrane, then the solutions cannot be relative to each other.

An Introduction to Life on Earth

Atoms, Molecules, and Life

Biological Molecules

Cell Structure and Function

Energy Flow in the Life of a Cell

Capturing Solar Energy: Photosynthesis

Harvesting Energy: Glycolysis and Cellular Respiration

Cellular Reproduction

Meiosis: the Basis of Sexual Reproduction

Patterns of Inheritance

DNA: The Molecule of Heredity

Gene Expression and Regulation

Biotechnology

Principles of Evolution

How Populations Evolve

The Origin of Species

The History of Life

Systematics: Seeking Order Amid Diversity

The Diversity of Prokaryotes and Viruses

The Diversity of Protists

The Diversity of Plants

The Diversity of Fungi

Animal Diversity I: Invertebrates

Animal Diversity Ii: Vertebrates

Animal Behavior

Population Growth and Regulation

Community Interactions

Energy Flow and Nutrient Cycling in Ecosystems

Earths Diverse Ecosystems

Conserving Earths Biodiversity

Homeostasis and the Organization of the Animal Body

Circulation

Respiration

Nutrition and Digestion

The Urinary System

Defenses Against Disease

Chemical Control of the Animal Body: the Endocrine System

The Nervous System

The Senses

Action and Support: the Muscles and Skeleton

Animal Reproduction

Animal Development

Plant Anatomy and Nutrient Transport

Plant Reproduction and Development

Plant Responses to the Environment

Filters

A freshwater protozoan, such as Paramecium, tends to because it lives in a environment.

The portion of the cell membrane is responsible for the isolating function of the membrane, whereas the portion regulates exchange and communication with the environment.