Question 1

When transpiration is proceeding at a high rate:

Accepted Answer

A)  stomata usually close. 
B)  guttation is at its greatest. 
C)  root pressure can push water to the top of a tall tree. 
D)  water is pulled into the roots by bulk flow. 
E)  hydraulic lift forces water into roots. 
A)  stomata usually close. 
B)  guttation is at its greatest. 
C)  root pressure can push water to the top of a tall tree. 
D)  water is pulled into the roots by bulk flow. 
E)  hydraulic lift forces water into roots.

Question 2

Which of the following statements concerning the uptake of K+ by guard cells is FALSE?

Accepted Answer

A)  Uptake of K+ is driven by a proton gradient. 
B)  Uptake of K+ is mediated by a red-light activated ATPase. 
C)  Uptake of K+ is accompanied by the uptake of Cl-. 
D)  Uptake of K+ is accompanied by the accumulation of malate. 
E)  Uptake of K+ creates the necessary water potential gradient. 
A)  Uptake of K+ is driven by a proton gradient. 
B)  Uptake of K+ is mediated by a red-light activated ATPase. 
C)  Uptake of K+ is accompanied by the uptake of Cl-. 
D)  Uptake of K+ is accompanied by the accumulation of malate. 
E)  Uptake of K+ creates the necessary water potential gradient.

Question 3

When water moving through the cortex via the apoplastic pathway reaches the endodermis:

Accepted Answer

A)  it continues through the apoplast. 
B)  it enters the cell walls. 
C)  apoplastic movement is stopped by the Casparian strips. 
D)  the symplastic pathway is blocked. 
E)  the transcellular pathway is blocked. 
A)  it continues through the apoplast. 
B)  it enters the cell walls. 
C)  apoplastic movement is stopped by the Casparian strips. 
D)  the symplastic pathway is blocked. 
E)  the transcellular pathway is blocked.

Question 4

In vascular plants, cavitation is the:

Accepted Answer

A)  rupture of water columns. 
B)  expulsion of air from water columns. 
C)  formation of air bubbles due to particulate matter. 
D)  reduction of surface tension at the meniscus spanning pores in the pit membrane. 
E)  filling of vessels with water vapor. 
A)  rupture of water columns. 
B)  expulsion of air from water columns. 
C)  formation of air bubbles due to particulate matter. 
D)  reduction of surface tension at the meniscus spanning pores in the pit membrane. 
E)  filling of vessels with water vapor.

Question 5

In the process of guttation, all of the following events occur EXCEPT:

Accepted Answer

A)  dew-like drops of water form at the tips of grass. 
B)  dew-like drops of water form at the tips of leaves. 
C)  water exudes through stomata that lack the ability to open and close. 
D)  water exudes through openings in structures called hydathodes. 
E)  water forms from the condensation of water from the air. 
A)  dew-like drops of water form at the tips of grass. 
B)  dew-like drops of water form at the tips of leaves. 
C)  water exudes through stomata that lack the ability to open and close. 
D)  water exudes through openings in structures called hydathodes. 
E)  water forms from the condensation of water from the air.

Question 6

The greater the vapor pressure difference between the intercellular spaces and the leaf surface, the faster is the rate of transpiration.

Accepted Answer

A) True 
 B)False

Question 7

In guard cells, _____ is the dominant osmoticum in the morning, and ______ is the dominant osmoticum in the afternoon.

Accepted Answer

A)  Cl-; sucrose 
B)  malate; K+ 
C)  K+, malate 
D)  sucrose; K+ 
E)  K+; sucrose 
A)  Cl-; sucrose 
B)  malate; K+ 
C)  K+, malate 
D)  sucrose; K+ 
E)  K+; sucrose

Question 8

A pressure chamber can be used to test the cohesion-tension theory by:

Accepted Answer

A)  measuring the tensile strength of water. 
B)  following the movement of colored water in the xylem. 
C)  measuring the shrinkage of a trunk caused by negative xylem pressure. 
D)  detecting the rate at which heated water moves through a plant. 
E)  determining the magnitude of the tension in a twig. 
A)  measuring the tensile strength of water. 
B)  following the movement of colored water in the xylem. 
C)  measuring the shrinkage of a trunk caused by negative xylem pressure. 
D)  detecting the rate at which heated water moves through a plant. 
E)  determining the magnitude of the tension in a twig.

Question 9

Transport of inorganic ions within the leaf occurs via the:

Accepted Answer

A)  apoplastic pathway only. 
B)  symplastic pathway only. 
C)  transpiration stream only. 
D)  apoplastic and symplastic pathways only. 
E)  transpiration stream and the apoplastic and symplastic pathways. 
A)  apoplastic pathway only. 
B)  symplastic pathway only. 
C)  transpiration stream only. 
D)  apoplastic and symplastic pathways only. 
E)  transpiration stream and the apoplastic and symplastic pathways.

Question 10

Which of the following indicates the correct sequence of tissues through which water moves from the soil into the root?

Accepted Answer

A)  Root hairs, endodermis, exodermis, cortical cells, vascular cylinder 
B)  Root hairs, endodermis, cortical cells, vascular cylinder, exodermis 
C)  Exodermis, endodermis, epidermis, vascular cylinder, cortical cells 
D)  Epidermis, exodermis, cortical cells, endodermis, vascular cylinder 
E)  Epidermis, endodermis, exodermis, cortical cells, vascular cylinder 
A)  Root hairs, endodermis, exodermis, cortical cells, vascular cylinder 
B)  Root hairs, endodermis, cortical cells, vascular cylinder, exodermis 
C)  Exodermis, endodermis, epidermis, vascular cylinder, cortical cells 
D)  Epidermis, exodermis, cortical cells, endodermis, vascular cylinder 
E)  Epidermis, endodermis, exodermis, cortical cells, vascular cylinder

Question 11

Which of the following statements about phloem unloading and transport is FALSE?

Accepted Answer

A)  Unloading can be apoplastic. 
B)  Unloading can be symplastic. 
C)  In young leaves and roots, unloading is probably passive. 
D)  In storage organs, energy is needed to accumulate sugars in sink cells. 
E)  In young leaves and roots, post-sieve-tube transport is passive. 
A)  Unloading can be apoplastic. 
B)  Unloading can be symplastic. 
C)  In young leaves and roots, unloading is probably passive. 
D)  In storage organs, energy is needed to accumulate sugars in sink cells. 
E)  In young leaves and roots, post-sieve-tube transport is passive.

Question 12

Once it has crossed the exodermis, water can pass into the root's vascular cylinder by the apoplastic pathway.

Accepted Answer

A) True 
 B)False

Question 13

According to the pressure-flow mechanism, sugars are transported in the phloem by flowing down a gradient of turgor pressure.

Accepted Answer

A) True 
 B)False

Question 14

Sucrose is translocated through sieve tubes:

Accepted Answer

A)  via active transport. 
B)  passively. 
C)  via facilitated diffusion. 
D)  via a proton-pumping mechanism. 
E)  via a combination of exocytosis and endocytosis. 
A)  via active transport. 
B)  passively. 
C)  via facilitated diffusion. 
D)  via a proton-pumping mechanism. 
E)  via a combination of exocytosis and endocytosis.

Question 15

Plants with crassulacean acid metabolism:

Accepted Answer

A)  open their stomata when conditions are favorable to transpiration. 
B)  convert CO2 to organic acids during the day. 
C)  convert organic acids to CO2 during the night. 
D)  are exemplified by members of the stonecrop family. 
E)  have a pathway for carbon flow much different from that of C4 plants. 
A)  open their stomata when conditions are favorable to transpiration. 
B)  convert CO2 to organic acids during the day. 
C)  convert organic acids to CO2 during the night. 
D)  are exemplified by members of the stonecrop family. 
E)  have a pathway for carbon flow much different from that of C4 plants.

Question 16

In roots, active transport of minerals is required for:

Accepted Answer

A)  uptake by epidermal cells only. 
B)  secretion into the vessels only. 
C)  transport through the apoplast and the symplast only. 
D)  uptake by epidermal cells and secretion into the vessels only. 
E)  uptake by epidermal cells, transport through the symplast, and secretion into the vessels. 
A)  uptake by epidermal cells only. 
B)  secretion into the vessels only. 
C)  transport through the apoplast and the symplast only. 
D)  uptake by epidermal cells and secretion into the vessels only. 
E)  uptake by epidermal cells, transport through the symplast, and secretion into the vessels.

Question 17

An air bubble in a vessel can be prevented from spreading to an adjacent vessel by:

Accepted Answer

A)  air seeding. 
B)  transport upward in the transpiration stream. 
C)  movement of a torus away from an aperture of a bordered pit-pair. 
D)  the surface tension of the meniscus spanning the pores of the bordered pit-pair membrane. 
E)  the filtering effect of the roots. 
A)  air seeding. 
B)  transport upward in the transpiration stream. 
C)  movement of a torus away from an aperture of a bordered pit-pair. 
D)  the surface tension of the meniscus spanning the pores of the bordered pit-pair membrane. 
E)  the filtering effect of the roots.

Question 18

The rate of transpiration is affected by stomatal movements and:

Accepted Answer

A)  air currents only. 
B)  humidity only. 
C)  temperature only. 
D)  temperature and air currents only. 
E)  temperature, humidity, and air currents. 
A)  air currents only. 
B)  humidity only. 
C)  temperature only. 
D)  temperature and air currents only. 
E)  temperature, humidity, and air currents.

Question 19

Which of the following statements concerning nocturnal transpiration is FALSE?

Accepted Answer

A)  For some species it constitutes a significant fraction of the daily water use. 
B)  It may enhance nutrient uptake. 
C)  It occurs when evaporation rates are higher than in the day. 
D)  It is due to stomata not closing completely in the dark. 
E)  It is found in many trees and shrubs. 
A)  For some species it constitutes a significant fraction of the daily water use. 
B)  It may enhance nutrient uptake. 
C)  It occurs when evaporation rates are higher than in the day. 
D)  It is due to stomata not closing completely in the dark. 
E)  It is found in many trees and shrubs.

Question 20

The stomata of many species open in the morning and close at night regardless of the amount of water available to the plant.

Accepted Answer

A) True 
 B)False

Exam 30: The Movement of Water and Solutes in Plants

When transpiration is proceeding at a high rate:

Which of the following statements concerning the uptake of K+ by guard cells is FALSE?

When water moving through the cortex via the apoplastic pathway reaches the endodermis:

In vascular plants, cavitation is the:

In the process of guttation, all of the following events occur EXCEPT:

The greater the vapor pressure difference between the intercellular spaces and the leaf surface, the faster is the rate of transpiration.

In guard cells, _____ is the dominant osmoticum in the morning, and ______ is the dominant osmoticum in the afternoon.

A pressure chamber can be used to test the cohesion-tension theory by:

Transport of inorganic ions within the leaf occurs via the:

Which of the following indicates the correct sequence of tissues through which water moves from the soil into the root?

Which of the following statements about phloem unloading and transport is FALSE?

Once it has crossed the exodermis, water can pass into the root's vascular cylinder by the apoplastic pathway.

According to the pressure-flow mechanism, sugars are transported in the phloem by flowing down a gradient of turgor pressure.

Sucrose is translocated through sieve tubes:

Plants with crassulacean acid metabolism:

In roots, active transport of minerals is required for:

An air bubble in a vessel can be prevented from spreading to an adjacent vessel by:

The rate of transpiration is affected by stomatal movements and:

Which of the following statements concerning nocturnal transpiration is FALSE?

The stomata of many species open in the morning and close at night regardless of the amount of water available to the plant.

Botany: an Introduction

The Molecular Composition of Plant Cells

The Plant Cell and the Cell Cycle

The Movement of Substances Into and Out of Cells

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 Dynamics of Communities and Ecosystems

Global Ecology

Filters

Which of the following statements concerning the uptake of K⁺ by guard cells is FALSE?

In guard cells, _ is the dominant osmoticum in the morning, and __ is the dominant osmoticum in the afternoon.