Question 1

What is the hypothesized role of carbohydrates in the plasma membrane?

Accepted Answer

A)  catalyzing chemical reactions 
B)  keeping the phospholipid tails aligned 
C)  recognizing molecules that interact with the cell 
D)  acting as a barrier to the passage of molecules 
E)  transporting molecules into the cell 
A)  catalyzing chemical reactions 
B)  keeping the phospholipid tails aligned 
C)  recognizing molecules that interact with the cell 
D)  acting as a barrier to the passage of molecules 
E)  transporting molecules into the cell

Question 2

Suppose a drop of dye is placed in one end of a tank of water. What happens next?

Accepted Answer

A)  Nothing happens because the molecules are at equilibrium. 
B)  The dye molecules and the water molecules move down their respective concentration gradients. 
C)  The dye molecules move from a region of high water potential to a region of low water potential. 
D)  The dye molecules move against a concentration gradient. 
E)  The water molecules move by osmosis. 
A)  Nothing happens because the molecules are at equilibrium. 
B)  The dye molecules and the water molecules move down their respective concentration gradients. 
C)  The dye molecules move from a region of high water potential to a region of low water potential. 
D)  The dye molecules move against a concentration gradient. 
E)  The water molecules move by osmosis.

Question 3

In plasmolysis:

Accepted Answer

A)  the vacuole become turgid. 
B)  the entire cell becomes turgid. 
C)  the cell wall shrivels into the center of the cytoplasm. 
D)  the plasma membrane pulls away from the cell wall. 
E)  the plasma membrane is pushed against the cell wall. 
A)  the vacuole become turgid. 
B)  the entire cell becomes turgid. 
C)  the cell wall shrivels into the center of the cytoplasm. 
D)  the plasma membrane pulls away from the cell wall. 
E)  the plasma membrane is pushed against the cell wall.

Question 4

An aquaporin is a:

Accepted Answer

A)  hole in a water molecule. 
B)  channel protein for water. 
C)  carrier protein for water. 
D)  protein that binds water inside the cytosol. 
E)  carbohydrate that binds water to prevent bursting of the cell. 
A)  hole in a water molecule. 
B)  channel protein for water. 
C)  carrier protein for water. 
D)  protein that binds water inside the cytosol. 
E)  carbohydrate that binds water to prevent bursting of the cell.

Question 5

Water moves from a region where water potential is higher to a region where it is lower.

Accepted Answer

A) True 
 B)False

Question 6

The portion of a transmembrane protein that is embedded in the hydrophobic interior of the bilayer is usually in the form of a(n):

Accepted Answer

A)  beta pleated sheet. 
B)  alpha helix. 
C)  alpha helix and beta pleated sheet combined. 
D)  extended polypeptide without secondary structure. 
E)  folded polypeptide without secondary structure. 
A)  beta pleated sheet. 
B)  alpha helix. 
C)  alpha helix and beta pleated sheet combined. 
D)  extended polypeptide without secondary structure. 
E)  folded polypeptide without secondary structure.

Question 7

A protein would most likely enter a cell by simple diffusion.

Accepted Answer

A) True 
 B)False

Question 8

Which of the following could be the water potential of a sucrose solution at atmospheric pressure and at sea level?

Accepted Answer

A)  100 MPa 
B)  100 bars 
C)  10 bars 
D)  0 bars 
E)  -10 MPa 
A)  100 MPa 
B)  100 bars 
C)  10 bars 
D)  0 bars 
E)  -10 MPa

Question 9

Once inside a cell, an ion will move from one part of the cytoplasm to another by diffusion.

Accepted Answer

A) True 
 B)False

Question 10

Pinocytosis is a form of endocytosis.

Accepted Answer

A) True 
 B)False

Question 11

Water potential is defined as the:

Accepted Answer

A)  tendency of water to enter a cell. 
B)  tendency of water to leave a cell. 
C)  mechanical energy of water. 
D)  kinetic energy of water. 
E)  potential energy of water. 
A)  tendency of water to enter a cell. 
B)  tendency of water to leave a cell. 
C)  mechanical energy of water. 
D)  kinetic energy of water. 
E)  potential energy of water.

Question 12

In the absence of other factors affecting water potential, water will move FROM a region of ______ TO a region of ______.

Accepted Answer

A)  low water concentration; high water concentration 
B)  low solute concentration; high solute concentration 
C)  low water potential; high water potential 
D)  low potential energy; high potential energy 
E)  low pressure; high pressure 
A)  low water concentration; high water concentration 
B)  low solute concentration; high solute concentration 
C)  low water potential; high water potential 
D)  low potential energy; high potential energy 
E)  low pressure; high pressure

Question 13

A "gate" is most directly associated with a:

Accepted Answer

A)  pinocytosis. 
B)  pump. 
C)  vesicle 
D)  carrier. 
E)  channel. 
A)  pinocytosis. 
B)  pump. 
C)  vesicle 
D)  carrier. 
E)  channel.

Question 14

The long-distance transport of sap in the phloem is an example of:

Accepted Answer

A)  simple diffusion. 
B)  facilitated diffusion. 
C)  pressure-driven bulk flow. 
D)  active transport. 
E)  exocytosis. 
A)  simple diffusion. 
B)  facilitated diffusion. 
C)  pressure-driven bulk flow. 
D)  active transport. 
E)  exocytosis.

Question 15

In the signal-transduction pathway involving Ca2+ ions in plants, which of the following occurs during the transduction step?

Accepted Answer

A)  The chemical signal binds to the receptor. 
B)  The Ca2+-calmodulin complex activates specific enzymes. 
C)  Clathrin binds to Ca2+ ions. 
D)  Calcium ions are released into the cytosol from the vacuole. 
E)  Calcium ions bind to calmodulin. 
A)  The chemical signal binds to the receptor. 
B)  The Ca2+-calmodulin complex activates specific enzymes. 
C)  Clathrin binds to Ca2+ ions. 
D)  Calcium ions are released into the cytosol from the vacuole. 
E)  Calcium ions bind to calmodulin.

Question 16

By definition, all proteins attached to protruding portions of transmembrane proteins are:

Accepted Answer

A)  transmembrane proteins. 
B)  integral proteins. 
C)  globular proteins. 
D)  peripheral proteins. 
E)  glycoproteins. 
A)  transmembrane proteins. 
B)  integral proteins. 
C)  globular proteins. 
D)  peripheral proteins. 
E)  glycoproteins.

Question 17

Which of the following is the best definition of osmosis?

Accepted Answer

A)  The net movement of glucose across a selectively permeable membrane. 
B)  The net movement of any substance down a solute concentration gradient. 
C)  The net movement of water across a selectively permeable membrane. 
D)  The net movement of water from a region of high water potential to a region of low water potential. 
E)  The net movement of water from a region of low water potential to a region of high water potential. 
A)  The net movement of glucose across a selectively permeable membrane. 
B)  The net movement of any substance down a solute concentration gradient. 
C)  The net movement of water across a selectively permeable membrane. 
D)  The net movement of water from a region of high water potential to a region of low water potential. 
E)  The net movement of water from a region of low water potential to a region of high water potential.

Question 18

Turgor pressure results most directly from:

Accepted Answer

A)  solutes moving out of a cell by osmosis. 
B)  solutes moving into a cell by osmosis. 
C)  water moving from one portion of the cytoplasm to another. 
D)  water moving into a cell by osmosis. 
E)  water moving out of a cell by osmosis. 
A)  solutes moving out of a cell by osmosis. 
B)  solutes moving into a cell by osmosis. 
C)  water moving from one portion of the cytoplasm to another. 
D)  water moving into a cell by osmosis. 
E)  water moving out of a cell by osmosis.

Question 19

Which of the following processes in plant cell membranes requires ATP?

Accepted Answer

A)  simple diffusion 
B)  facilitated diffusion 
C)  osmosis 
D)  passive cotransport 
E)  active transport 
A)  simple diffusion 
B)  facilitated diffusion 
C)  osmosis 
D)  passive cotransport 
E)  active transport

Question 20

Symport is a transport system in which the transport of one solute:

Accepted Answer

A)  occurs via a vesicle. 
B)  occurs without the simultaneous transport of another solute. 
C)  depends on the transport of another solute in the opposite direction. 
D)  depends on the transport of another solute in the same direction. 
E)  depends on the opening of a "gate" in the carrier protein. 
A)  occurs via a vesicle. 
B)  occurs without the simultaneous transport of another solute. 
C)  depends on the transport of another solute in the opposite direction. 
D)  depends on the transport of another solute in the same direction. 
E)  depends on the opening of a "gate" in the carrier protein.

Exam 4: The Movement of Substances Into and Out of Cells

What is the hypothesized role of carbohydrates in the plasma membrane?

Suppose a drop of dye is placed in one end of a tank of water. What happens next?

In plasmolysis:

An aquaporin is a:

Water moves from a region where water potential is higher to a region where it is lower.

The portion of a transmembrane protein that is embedded in the hydrophobic interior of the bilayer is usually in the form of a(n):

A protein would most likely enter a cell by simple diffusion.

Which of the following could be the water potential of a sucrose solution at atmospheric pressure and at sea level?

Once inside a cell, an ion will move from one part of the cytoplasm to another by diffusion.

Pinocytosis is a form of endocytosis.

Water potential is defined as the:

In the absence of other factors affecting water potential, water will move FROM a region of ______ TO a region of ______.

A "gate" is most directly associated with a:

The long-distance transport of sap in the phloem is an example of:

In the signal-transduction pathway involving Ca2+ ions in plants, which of the following occurs during the transduction step?

By definition, all proteins attached to protruding portions of transmembrane proteins are:

Which of the following is the best definition of osmosis?

Turgor pressure results most directly from:

Which of the following processes in plant cell membranes requires ATP?

Symport is a transport system in which the transport of one solute:

Botany: an Introduction

The Molecular Composition of Plant Cells

The Plant Cell and the Cell Cycle

The Flow of Energy

Respiration

Photosynthesis, Light, and Life

Sexual Reproduction and Heredity

The Chemistry of Heredity and Gene Expression

Recombinant Dna Technology, Plant Biotechnology, and Genomics

The Process of Evolution

Systematics: the Science of Biological Diversity

Prokaryotes and Viruses

Fungi

Protists: Algae and Heterotrophic Protists

Bryophytes

Seedless Vascular Plants

Gymnosperms

Introduction to the Angiosperms

Evolution of the Angiosperms

Plants and People

Early Development of the Plant Body

Cells and Tissues of the Plant Body

The Root: Structure and Development

The Shoot: Primary Structure and Development

Secondary Growth in Stems

Regulating Growth and Development: the Plant Hormones

External Factors and Plant Growth

Plant Nutrition and Soils

The Movement of Water and Solutes in Plants

The Dynamics of Communities and Ecosystems

Global Ecology

Filters

In the absence of other factors affecting water potential, water will move FROM a region of TO a region of .

In the signal-transduction pathway involving Ca²⁺ ions in plants, which of the following occurs during the transduction step?