Question 1

The energy that drives water into root cells comes most directly from

Accepted Answer

A)  ATP. 
B)  the sun. 
C)  NADPH+. 
D)  bulk flow. 
E)  chloroplasts. 
A)  ATP. 
B)  the sun. 
C)  NADPH+. 
D)  bulk flow. 
E)  chloroplasts.

Question 2

Aquaporins

Accepted Answer

A)  actively pump water. 
B)  change the direction of water transport. 
C)  facilitate osmosis. 
D)  are needed for the apoplastic transport of water in roots. 
E)  Both b and c 
A)  actively pump water. 
B)  change the direction of water transport. 
C)  facilitate osmosis. 
D)  are needed for the apoplastic transport of water in roots. 
E)  Both b and c

Question 3

When a tree is girdled, the bark swells in the region _______ the girdle, and the _______ die before the rest of the tree.

Accepted Answer

A)  below; roots 
B)  below; branches 
C)  below; leaves 
D)  above; roots 
E)  above; branches 
A)  below; roots 
B)  below; branches 
C)  below; leaves 
D)  above; roots 
E)  above; branches

Question 4

Explain how transpiration, cohesion, and tension work together to move water in a large plant.

Accepted Answer

The transpiration-cohesion-tension mecha

Question 5

Differentiate between source and sink tissues. What happens relative to phloem in each?

Accepted Answer

Source tissues produce sugars in excess

Question 6

Which of the following causes the root pressure that moves water upward in plant xylem?

Accepted Answer

A)  Negative water potential in the xylem sap 
B)  High pressure potential of water in the soil 
C)  Movement of water from root cells into the soil 
D)  Active transport of minerals from soil to root cells 
E)  High atmospheric humidity 
A)  Negative water potential in the xylem sap 
B)  High pressure potential of water in the soil 
C)  Movement of water from root cells into the soil 
D)  Active transport of minerals from soil to root cells 
E)  High atmospheric humidity

Question 7

Which property accounts for the movement of water upward through a narrow tube?

Accepted Answer

A)  Cohesion of water molecules via hydrogen bonding 
B)  Negative water potential in the xylem 
C)  Active transport of water molecules 
D)  Passive osmosis of water following ion movement 
E)  Pumping of water into the phloem 
A)  Cohesion of water molecules via hydrogen bonding 
B)  Negative water potential in the xylem 
C)  Active transport of water molecules 
D)  Passive osmosis of water following ion movement 
E)  Pumping of water into the phloem

Question 8

Pumping protons (H+) out of a cell can trigger the movement of

Accepted Answer

A)  K+ out of the cell and Cl- into the cell. 
B)  K+ into the cell and Cl- out of the cell. 
C)  both K+ and Cl- out of the cell. 
D)  both K+ and Cl- into the cell. 
E)  K+ into the cell, with no movement of Cl-. 
A)  K+ out of the cell and Cl- into the cell. 
B)  K+ into the cell and Cl- out of the cell. 
C)  both K+ and Cl- out of the cell. 
D)  both K+ and Cl- into the cell. 
E)  K+ into the cell, with no movement of Cl-.

Question 9

The pressure flow model of translocation depends entirely on the existence of mechanisms for loading sugars into phloem at the _______ regions and for unloading them at the _______ regions.

Accepted Answer

A)  sink; sink 
B)  sink; source 
C)  source; source 
D)  source; sink 
E)  source; source or sink 
A)  sink; sink 
B)  sink; source 
C)  source; source 
D)  source; sink 
E)  source; source or sink

Question 10

Plant cells that lack cell walls, called protoplasts, may be prepared by the incubation of plant tissues with enzymes that destroy the cell wall. Protoplasts are much more sensitive than intact plant cells to the solute concentration of the solution in which they are suspended. Why?

Accepted Answer

A)  The lack of a cell wall prevents the cells from shrinking. 
B)  The lack of a cell wall prevents osmosis. 
C)  Cells that lack the cell wall cannot develop a pressure potential to counter the osmotic potential and could burst when placed in hypertonic solutions. 
D)  Cells that lack the cell wall cannot develop a pressure potential to counter the osmotic potential when placed in hypotonic solutions. 
E)  The cell wall contains aquaporins. 
A)  The lack of a cell wall prevents the cells from shrinking. 
B)  The lack of a cell wall prevents osmosis. 
C)  Cells that lack the cell wall cannot develop a pressure potential to counter the osmotic potential and could burst when placed in hypertonic solutions. 
D)  Cells that lack the cell wall cannot develop a pressure potential to counter the osmotic potential when placed in hypotonic solutions. 
E)  The cell wall contains aquaporins.

Question 11

Guttation is most commonly observed under conditions of _______ atmospheric humidity and _______ soil water.

Accepted Answer

A)  high; plentiful 
B)  low; plentiful 
C)  high; little 
D)  low; little 
E)  varying; plentiful 
A)  high; plentiful 
B)  low; plentiful 
C)  high; little 
D)  low; little 
E)  varying; plentiful

Question 12

The plasma membrane of plant cells

Accepted Answer

A)  contains a Na+/K+-ATPase. 
B)  maintains a positive membrane potential across the membrane. 
C)  contains an ATP-dependent proton pump. 
D)  does not carry out indirect active transport. 
E)  makes ATP. 
A)  contains a Na+/K+-ATPase. 
B)  maintains a positive membrane potential across the membrane. 
C)  contains an ATP-dependent proton pump. 
D)  does not carry out indirect active transport. 
E)  makes ATP.

Question 13

In which of the following water potential conditions will water move from the root hairs through the cortex to the xylem?

Accepted Answer

A)  Root hairs = 0, cortex = 0, xylem = 0 
B)  Root hairs = -1, cortex = -1, xylem = -1 
C)  Root hairs = -2, cortex = -1, xylem = 0 
D)  Root hairs = 0, cortex = +1, xylem = +2 
E)  Root hairs = 0, cortex = -1, xylem = -2 
A)  Root hairs = 0, cortex = 0, xylem = 0 
B)  Root hairs = -1, cortex = -1, xylem = -1 
C)  Root hairs = -2, cortex = -1, xylem = 0 
D)  Root hairs = 0, cortex = +1, xylem = +2 
E)  Root hairs = 0, cortex = -1, xylem = -2

Question 14

The active transport of sucrose molecules from a leaf's apoplast to its phloem requires that the sucrose be cotransported with

Accepted Answer

A)  H+. 
B)  amino acids. 
C)  K+. 
D)  Cl-. 
E)  water. 
A)  H+. 
B)  amino acids. 
C)  K+. 
D)  Cl-. 
E)  water.

Question 15

If the concentration of a solute (for example, sucrose) is higher inside a cell than outside it,

Accepted Answer

A)  sucrose may be taken up by the cell without the expenditure of energy. 
B)  sucrose may diffuse passively out of the cell. 
C)  the diffusion of sucrose out of the cell will require energy. 
D)  sucrose may be taken up by primary active transport. 
E)  water will move out of the cell. 
A)  sucrose may be taken up by the cell without the expenditure of energy. 
B)  sucrose may diffuse passively out of the cell. 
C)  the diffusion of sucrose out of the cell will require energy. 
D)  sucrose may be taken up by primary active transport. 
E)  water will move out of the cell.

Question 16

Which of the following statements about water transport is true?

Accepted Answer

A)  Root pressure is sufficient to drive xylem sap movement. 
B)  Bulk flow is not a mechanism by which water and minerals are transported. 
C)  The cohesive nature of water is central to water movement in a plant. 
D)  Water transport is an active process. 
E)  None of the above 
A)  Root pressure is sufficient to drive xylem sap movement. 
B)  Bulk flow is not a mechanism by which water and minerals are transported. 
C)  The cohesive nature of water is central to water movement in a plant. 
D)  Water transport is an active process. 
E)  None of the above

Question 17

The fact that water transport continues as long as leaves are alive and active indicates that

Accepted Answer

A)  leaves pump water. 
B)  leaves are necessary for transport of water. 
C)  roots are active. 
D)  water is not needed for leaves to remain alive. 
E)  sieve tube elements are inactive. 
A)  leaves pump water. 
B)  leaves are necessary for transport of water. 
C)  roots are active. 
D)  water is not needed for leaves to remain alive. 
E)  sieve tube elements are inactive.

Question 18

The facilitated diffusion of ions from the soil solution into root cells requires

Accepted Answer

A)  that the concentration of ions at the root cells be the same outside and inside. 
B)  that the concentration of ions outside the root cells be lower than the concentration inside. 
C)  the expenditure of ATP. 
D)  specific channel proteins in the membranes. 
E)  cellular respiration. 
A)  that the concentration of ions at the root cells be the same outside and inside. 
B)  that the concentration of ions outside the root cells be lower than the concentration inside. 
C)  the expenditure of ATP. 
D)  specific channel proteins in the membranes. 
E)  cellular respiration.

Question 19

When the ion concentration inside root cells is higher than the concentration in the soil solution, ions in the soil solution can enter root cells by means of

Accepted Answer

A)  active transport only. 
B)  simple diffusion only. 
C)  simple diffusion and facilitated diffusion. 
D)  facilitated diffusion and active transport. 
E)  simple diffusion and active transport. 
A)  active transport only. 
B)  simple diffusion only. 
C)  simple diffusion and facilitated diffusion. 
D)  facilitated diffusion and active transport. 
E)  simple diffusion and active transport.

Question 20

A more negative water potential in the xylem of the root than in the soil causes water to be drawn into the xylem, generating a force called _______.

Accepted Answer

The answer of A more negative water potential in the...

Exam 35: Transport in Plants

The energy that drives water into root cells comes most directly from

Aquaporins

When a tree is girdled, the bark swells in the region _______ the girdle, and the _______ die before the rest of the tree.

Explain how transpiration, cohesion, and tension work together to move water in a large plant.

Differentiate between source and sink tissues. What happens relative to phloem in each?

Which of the following causes the root pressure that moves water upward in plant xylem?

Which property accounts for the movement of water upward through a narrow tube?

Pumping protons (H+) out of a cell can trigger the movement of

The pressure flow model of translocation depends entirely on the existence of mechanisms for loading sugars into phloem at the _______ regions and for unloading them at the _______ regions.

Plant cells that lack cell walls, called protoplasts, may be prepared by the incubation of plant tissues with enzymes that destroy the cell wall. Protoplasts are much more sensitive than intact plant cells to the solute concentration of the solution in which they are suspended. Why?

Guttation is most commonly observed under conditions of _______ atmospheric humidity and _______ soil water.

The plasma membrane of plant cells

In which of the following water potential conditions will water move from the root hairs through the cortex to the xylem?

The active transport of sucrose molecules from a leaf's apoplast to its phloem requires that the sucrose be cotransported with

If the concentration of a solute (for example, sucrose) is higher inside a cell than outside it,

Which of the following statements about water transport is true?

The fact that water transport continues as long as leaves are alive and active indicates that

The facilitated diffusion of ions from the soil solution into root cells requires

When the ion concentration inside root cells is higher than the concentration in the soil solution, ions in the soil solution can enter root cells by means of

A more negative water potential in the xylem of the root than in the soil causes water to be drawn into the xylem, generating a force called _______.

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 Membranes

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

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

Community Ecology

Ecosystems and Global Ecology

Conservation Biology

Filters

When a tree is girdled, the bark swells in the region _ the girdle, and the _ die before the rest of the tree.

Pumping protons (H⁺) out of a cell can trigger the movement of

The pressure flow model of translocation depends entirely on the existence of mechanisms for loading sugars into phloem at the _ regions and for unloading them at the _ regions.

Guttation is most commonly observed under conditions of _ atmospheric humidity and _ soil water.