Question 1

How does water move so rapidly across plant cell membranes?

Accepted Answer

Aquaporins are channel protein

Question 2

The most prominent known role in the opening and closing of stomata is played by____ ions.

Accepted Answer

A)  Ca2+ 
B)  Cl- 
C)  K+ 
D)  NH4+ 
E)  Na+ 
A)  Ca2+ 
B)  Cl- 
C)  K+ 
D)  NH4+ 
E)  Na+

Question 3

The movement of NH4+ions into a cell down an electrochemical gradient created by H+pumping is an example of ____.

Accepted Answer

A)  an ion pump 
B)  passive diffusion 
C)  facilitated diffusion 
D)  secondary active transport 
E)  passive transport 
A)  an ion pump 
B)  passive diffusion 
C)  facilitated diffusion 
D)  secondary active transport 
E)  passive transport

Question 4

Suppose a living plant cell has ψ = ψS = -0.5 MPa. If the plant cell is placed into a beaker filled with a solution with ψ = 0, then the cell should ____.

Accepted Answer

A)  take up water until it bursts 
B)  lose water until its ψ = ψ of the solution 
C)  take up water until within the cell ψP = 0 
D)  take up water until its ψ = ψS of the solution 
E)  lose water until its ψS = its ψP 
A)  take up water until it bursts 
B)  lose water until its ψ = ψ of the solution 
C)  take up water until within the cell ψP = 0 
D)  take up water until its ψ = ψS of the solution 
E)  lose water until its ψS = its ψP

Question 5

Experiments have shown that xylem sap transport peaks ____.

Accepted Answer

A)  in the early morning 
B)  by mid-morning 
C)  at midday 
D)  in the evening 
E)  overnight 
A)  in the early morning 
B)  by mid-morning 
C)  at midday 
D)  in the evening 
E)  overnight

Question 6

The major cost to plants for having cuticle-covered epidermis in the shoot system to reduce water loss is reduced ____ uptake.

Accepted Answer

A)  carbon dioxide 
B)  potassium 
C)  nitrogen 
D)  calcium 
E)  oxygen 
A)  carbon dioxide 
B)  potassium 
C)  nitrogen 
D)  calcium 
E)  oxygen

Question 7

Stomata close when ____ guard cells and they become ____.

Accepted Answer

A)  active transport pumps H+into; turgid 
B)  active transport of H+stops in; flaccid 
C)  active transport pumps H+out of; turgid 
D)  active transport pumps H+into; flaccid 
E)  active transport of H+stops in; turgid 
A)  active transport pumps H+into; turgid 
B)  active transport of H+stops in; flaccid 
C)  active transport pumps H+out of; turgid 
D)  active transport pumps H+into; flaccid 
E)  active transport of H+stops in; turgid

Question 8

Water that moves through nonliving regions of root, such as air spaces in root tissue, is following the ____.

Accepted Answer

A)  symplastic pathway only 
B)  transmembrane and symplastic pathways 
C)  transmembrane pathway only 
D)  apoplastic, transmembrane, and symplastic pathways 
E)  apoplastic pathway only 
A)  symplastic pathway only 
B)  transmembrane and symplastic pathways 
C)  transmembrane pathway only 
D)  apoplastic, transmembrane, and symplastic pathways 
E)  apoplastic pathway only

Question 9

The hypothesis that high pressure forces phloem sap to flow was tested and supported by studies using ____.

Accepted Answer

A)  caterpillars 
B)  radiolabeled hormones 
C)  vacuum chambers 
D)  aphids 
E)  radiolabeled sugars 
A)  caterpillars 
B)  radiolabeled hormones 
C)  vacuum chambers 
D)  aphids 
E)  radiolabeled sugars

Question 10

Phloem sap would not be expected to contain ____.

Accepted Answer

A)  carbohydrates 
B)  hormones 
C)  water 
D)  amino acids 
E)  lipids 
A)  carbohydrates 
B)  hormones 
C)  water 
D)  amino acids 
E)  lipids

Question 11

In herbaceous plants, the stress-related closing of stomata is regulated by ____.

Accepted Answer

A)  sunlight 
B)  ion concentrations in the xylem 
C)  CO2concentration 
D)  O2concentration 
E)  abscisic acid 
A)  sunlight 
B)  ion concentrations in the xylem 
C)  CO2concentration 
D)  O2concentration 
E)  abscisic acid

Question 12

What is the ψP of a living plant cell that has ψ = -0.2 MPa and ψS = -0.4 MPa?

Accepted Answer

A)  ψP = -0.6 MPa 
B)  ψP = 0.08 MPa 
C)  ψP = -0.2 MPa 
D)  ψP = 0.2 MPa 
E)  ψP = 0.5 MPa 
A)  ψP = -0.6 MPa 
B)  ψP = 0.08 MPa 
C)  ψP = -0.2 MPa 
D)  ψP = 0.2 MPa 
E)  ψP = 0.5 MPa

Question 13

The movement of xylem sap is best described from the ____ to the ____.

Accepted Answer

A)  shoot system; root system 
B)  sinks; sources 
C)  root system; shoot system 
D)  sources; sinks 
E)  shoot system; sinks 
A)  shoot system; root system 
B)  sinks; sources 
C)  root system; shoot system 
D)  sources; sinks 
E)  shoot system; sinks

Question 14

Stomata open when K+concentration in guard cells ____, followed by water ____ the guard cells by osmosis.

Accepted Answer

A)  increases; entering 
B)  decreases; entering 
C)  decreases; leaving 
D)  increases; leaving 
E)  increases H+; leaving 
A)  increases; entering 
B)  decreases; entering 
C)  decreases; leaving 
D)  increases; leaving 
E)  increases H+; leaving

Question 15

Active transport in plant root cells requires that those cells have access to O2. Normally there is enough O2available in air pockets in the soil, but flooded soil has very little O2. Thus, unless they have special adaptations, plants in flooded soil effectively have no active transport in their roots. Which of the following should you expect to occur for trees without special adaptations to flooding after several days in flooded soil?

Accepted Answer

A)  excess uptake of water and minerals in the xylem only 
B)  wilting of their leaves 
C)  bursting of leaf cells due to excess water flow 
D)  excess water pushed out at the margins of their leaves only 
E)  excess uptake of water and minerals in the xylem, and excess water pushed out at the margins of their leaves 
A)  excess uptake of water and minerals in the xylem only 
B)  wilting of their leaves 
C)  bursting of leaf cells due to excess water flow 
D)  excess water pushed out at the margins of their leaves only 
E)  excess uptake of water and minerals in the xylem, and excess water pushed out at the margins of their leaves

Question 16

In a living plant cell in a living plant, you would expect to find protons ____.

Accepted Answer

A)  moving out of the cell via passive diffusion 
B)  being actively pumped into the cell 
C)  moving out of the cell via facilitated diffusion 
D)  being actively pumped out of the cell 
E)  moving into the cell via passive diffusion 
A)  moving out of the cell via passive diffusion 
B)  being actively pumped into the cell 
C)  moving out of the cell via facilitated diffusion 
D)  being actively pumped out of the cell 
E)  moving into the cell via passive diffusion

Question 17

In plants, the long-distance transport of substances is called transpiration.

Accepted Answer

A) True 
 B)False

Question 18

Theoretically, based on the cohesion-tension mechanism, the maximum height for the tallest trees should be about ____.

Accepted Answer

A)  50 ft 
B)  130 m 
C)  6 ft 
D)  3 m 
E)  75 m 
A)  50 ft 
B)  130 m 
C)  6 ft 
D)  3 m 
E)  75 m

Question 19

In some plants, companion cells become modified into phloem cells that facilitate the short-distance transport of various organic solutes from the symplast into the apoplast.

Accepted Answer

A) True 
 B)False

Question 20

Researchers in Finland determined the function of NAC proteins in the formation of ____.

Accepted Answer

A)  glucose 
B)  root hairs 
C)  chloroplasts 
D)  xylem 
E)  sieve tube elements 
A)  glucose 
B)  root hairs 
C)  chloroplasts 
D)  xylem 
E)  sieve tube elements

Exam 34: Transport in Plants

How does water move so rapidly across plant cell membranes?

The most prominent known role in the opening and closing of stomata is played by____ ions.

The movement of NH4+ions into a cell down an electrochemical gradient created by H+pumping is an example of ____.

Suppose a living plant cell has ψ = ψS = -0.5 MPa. If the plant cell is placed into a beaker filled with a solution with ψ = 0, then the cell should ____.

Experiments have shown that xylem sap transport peaks ____.

The major cost to plants for having cuticle-covered epidermis in the shoot system to reduce water loss is reduced ____ uptake.

Stomata close when ____ guard cells and they become ____.

Water that moves through nonliving regions of root, such as air spaces in root tissue, is following the ____.

The hypothesis that high pressure forces phloem sap to flow was tested and supported by studies using ____.

Phloem sap would not be expected to contain ____.

In herbaceous plants, the stress-related closing of stomata is regulated by ____.

What is the ψP of a living plant cell that has ψ = -0.2 MPa and ψS = -0.4 MPa?

The movement of xylem sap is best described from the ____ to the ____.

Stomata open when K+concentration in guard cells ____, followed by water ____ the guard cells by osmosis.

In a living plant cell in a living plant, you would expect to find protons ____.

In plants, the long-distance transport of substances is called transpiration.

Theoretically, based on the cohesion-tension mechanism, the maximum height for the tallest trees should be about ____.

In some plants, companion cells become modified into phloem cells that facilitate the short-distance transport of various organic solutes from the symplast into the apoplast.

Researchers in Finland determined the function of NAC proteins in the formation of ____.

Introduction to Biological Concepts and Research

Life, Chemistry, and Water

Biological Molecules: the Carbon Compounds of Life

Cells

Membranes and Transport

Energy, Enzymes, and Biological Reactions

Cellular Respiration: Harvesting Chemical Energy

Photosynthesis

Cell Communication

Cell Division and Mitosis

Meiosis: the Cellular Basis of Sexual Reproduction

Mendel, Genes, and Inheritance

Genes, Chromosomes, and Human Genetics

Dna Structure, Replication, and Organization

Gene Expression: From Dna to Protein

Regulation of Gene Expression

Bacterial and Viral Genetics

Dna Technology: Making and Using Genetically Altered Organisms, and Other Applications

Genomes and Proteomes

The Development of Evolutionary Thought

Microevolution: Genetic Changes Within Populations

Speciation

Paleobiology and Macroevolution

Systematic Biology: Phylogeny and Classification

The Origin of Life

Prokaryotes and Viruses

Protists

Seedless Plants

Seed Plants

Fungi

Animal Phylogeny, Acoelomates, and Protostomes

Deuterostomes: Vertebrates and Their Closest Relatives

The Plant Body

Plant Nutrition

Reproduction and Development in Flowering Plants

Plant Signals and Responses to the Environment

Introduction to Animal Organization and Physiology

Information Flow and the Neuron

Nervous Systems

Sensory Systems

The Endocrine System

Muscles, Bones, and Body Movements

The Circulatory System

Defenses Against Disease

Gas Exchange: the Respiratory System

Digestive Systems and Animal Nutrition

Regulating the Internal Environment: Osmoregulation, Excretion, and Thermoregulation

Animal Reproduction

Animal Development

Ecology and the Biosphere

Population Ecology

Population Interactions and Community Ecology

Ecosystems

Biodiversity and Conservation Biology

Animal Behavior

Filters

The movement of NH₄⁺ions into a cell down an electrochemical gradient created by H⁺pumping is an example of ____.

Stomata close when guard cells and they become .

The movement of xylem sap is best described from the to the .

Stomata open when K⁺concentration in guard cells , followed by water the guard cells by osmosis.