Question 1

Which of the following statements concerning the polymer trapping mechanism is FALSE?

Accepted Answer

A) It is a type of symplastic loading. 
B) The companion cells are intermediary cells. 
C) Sucrose is used to synthesize polymers. 
D) Raffinose and stachyose are actively transported into the sieve tubes. 
E) Energy is used to create a concentration difference between the mesophyll and the phloem. 
A) It is a type of symplastic loading. 
B) The companion cells are intermediary cells. 
C) Sucrose is used to synthesize polymers. 
D) Raffinose and stachyose are actively transported into the sieve tubes. 
E) Energy is used to create a concentration difference between the mesophyll and the phloem.

Question 2

The major difference between the symplastic and the transcellular pathways of the root is that the transcellular pathway involves:

Accepted Answer

A) plasmodesmata. 
B) protoplasts. 
C) plasma membranes. 
D) cell walls. 
E) vacuoles. 
A) plasmodesmata. 
B) protoplasts. 
C) plasma membranes. 
D) cell walls. 
E) vacuoles.

Question 3

Nocturnal transpiration occurs in CAM plants but not C3 plants.

Accepted Answer

A) True 
 B)False

Question 4

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

Question 5

Which of the following is NOT evidence supporting the role of phloem in sugar transport?

Accepted Answer

A) Honeydew contains amino acids but not sucrose. 
B) 14C-labeled sucrose is transported in sieve tubes. 
C) The exudate from the stylets of feeding aphids is mainly sucrose. 
D) Radioactive assimilates are transported in the phloem. 
E) When a tree is girdled, the bark above the ring becomes swollen. 
A) Honeydew contains amino acids but not sucrose. 
B) 14C-labeled sucrose is transported in sieve tubes. 
C) The exudate from the stylets of feeding aphids is mainly sucrose. 
D) Radioactive assimilates are transported in the phloem. 
E) When a tree is girdled, the bark above the ring becomes swollen.

Question 6

Which of the following is/are present in the highest concentration in sieve-tube sap?

Accepted Answer

A) glucose 
B) amino acids 
C) magnesium 
D) sorbitol 
E) sucrose 
A) glucose 
B) amino acids 
C) magnesium 
D) sorbitol 
E) sucrose

Question 7

In the process of stomatal closing, which of the following events occurs first?

Accepted Answer

A) Water moves out of guard cells. 
B) Water moves into guard cells. 
C) Guard cell turgor pressure decreases. 
D) Guard cell solute concentration declines. 
E) Guard cell water potential increases. 
A) Water moves out of guard cells. 
B) Water moves into guard cells. 
C) Guard cell turgor pressure decreases. 
D) Guard cell solute concentration declines. 
E) Guard cell water potential increases.

Question 8

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 9

A dry breeze increases the rate of transpiration mainly because it:

Accepted Answer

A) cools the leaf. 
B) warms the leaf. 
C) increases the CO2 gradient across the leaf surface. 
D) decreases the CO2 gradient across the leaf surface. 
E) increases the vapor pressure difference across the leaf surface. 
A) cools the leaf. 
B) warms the leaf. 
C) increases the CO2 gradient across the leaf surface. 
D) decreases the CO2 gradient across the leaf surface. 
E) increases the vapor pressure difference across the leaf surface.

Question 10

An ion moving across the root via the symplastic pathway would NOT pass across the:

Accepted Answer

A) plasma membrane of the epidermis. 
B) epidermal cell protoplast. 
C) cell walls of the exodermis. 
D) plasmodesmata in the epidermal-cortical cell walls. 
E) endodermis. 
A) plasma membrane of the epidermis. 
B) epidermal cell protoplast. 
C) cell walls of the exodermis. 
D) plasmodesmata in the epidermal-cortical cell walls. 
E) endodermis.

Question 11

The cuticle is largely impermeable to both water and carbon dioxide.

Accepted Answer

A) True 
 B)False

Question 12

As a consequence of girdling a tree:

Accepted Answer

A) its leaves stop exporting solutes. 
B) its leaves stop importing solutes. 
C) the bark above the girdle swells. 
D) the bark above the girdle dies. 
E) the bark begins to act as a source. 
A) its leaves stop exporting solutes. 
B) its leaves stop importing solutes. 
C) the bark above the girdle swells. 
D) the bark above the girdle dies. 
E) the bark begins to act as a source.

Question 13

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 14

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 15

Which of the following statements about xylem and phloem is FALSE?

Accepted Answer

A) They are closely associated spatially. 
B) They are closely associated functionally. 
C) They form a continuous vascular system. 
D) They are involved in long-distance transport. 
E) Xylem transports only water, and phloem transports only nutrients. 
A) They are closely associated spatially. 
B) They are closely associated functionally. 
C) They form a continuous vascular system. 
D) They are involved in long-distance transport. 
E) Xylem transports only water, and phloem transports only nutrients.

Question 16

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 17

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 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

Phototropins are:

Accepted Answer

A) osmoticums. 
B) photoreceptors. 
C) microfibrils. 
D) enzymes. 
E) active-transport proteins. 
A) osmoticums. 
B) photoreceptors. 
C) microfibrils. 
D) enzymes. 
E) active-transport proteins.

Question 20

Calcium is a phloem-immobile element.

Accepted Answer

A) True 
 B)False

Exam 30: The Movement of Water and Solutes in Plants

Which of the following statements concerning the polymer trapping mechanism is FALSE?

The major difference between the symplastic and the transcellular pathways of the root is that the transcellular pathway involves:

Nocturnal transpiration occurs in CAM plants but not C3 plants.

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

Which of the following is NOT evidence supporting the role of phloem in sugar transport?

Which of the following is/are present in the highest concentration in sieve-tube sap?

In the process of stomatal closing, which of the following events occurs first?

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

A dry breeze increases the rate of transpiration mainly because it:

An ion moving across the root via the symplastic pathway would NOT pass across the:

The cuticle is largely impermeable to both water and carbon dioxide.

As a consequence of girdling a tree:

When transpiration is proceeding at a high rate:

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 xylem and phloem is FALSE?

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

Sucrose is translocated through sieve tubes:

The rate of transpiration is affected by stomatal movements and:

Phototropins are:

Calcium is a phloem-immobile element.

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

Nocturnal transpiration occurs in CAM plants but not C₃ plants.