AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 35: Plant Structure, Growth, and Development
Name
Period
Chapter 35: Plant Structure, Growth, and Development
In this unit on plants, the challenge for students will be to learn the new vocabulary. As we work
through this unit, you will find an emphasis on labeling and explaining plant diagrams and specific
directions for which terms you should know.
Concept 35.1 The plant body has a hierarchy of organs, tissues, and cells
1.
This concept is organized into three sections—plant organs, tissues, and cells. Begin by
defining a tissue and an organ.
2.
The three plant organs are
3.
On Figure 35.2, label the shoot system, root system, apical bud, axillary bud, and root system.
4.
Define root and then explain the difference between a taproot and lateral roots.
,
, and
.
Root
Taproot and lateral roots
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Chapter 35: Plant Structure, Growth, and Development
AP Biology Reading Guide
Fred and Theresa Holtzclaw
5.
This photograph shows the root hairs of a radish. What is the function of root hairs?
6.
What is the advantage of apical dominance to a plant?
7.
The main function of a leaf is
8.
What are five additional functions that modified leaves can perform?
9.
Plants have three types of tissues. Place the name of each tissue type and its function in the
table below.
Tissue type
.
Function
10.
What is the function of the cuticle?
11.
Xylem conducts
12.
Xylem transport tends to be in one direction, but phloem transport is more complicated. Explain
the pattern of sugar flow in phloem tissue.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 35: Plant Structure, Growth, and Development
13.
The two major tissues of the ground tissue system are pith and cortex. Where are they found in
the plant?
14.
Plants have five major types of cells. Below you will find a picture of each cell type. Give the
major function of each cell type. Specific questions may follow your general description of the
cell type.
Parenchyma cells
Function
Collenchyma cells
Sclerenchyma cells
Xylem cells
Label vessel elements, tracheids, and pits.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 35: Plant Structure, Growth, and Development
Phloem cells
Label companion cell, sieve tube element, and sieve plate.
15.
Compare and contrast the following structures:
Tracheids and vessel elements
Sieve tube elements and companion cells
16.
At the end of this first extensive concept, do not lose sight of the big picture. Complete the
following summary charts.
The three plant organs are
The three basic plant tissues are
The five basic plant cells are
Concept 35.2 Meristems generate cells for new plant organs
17.
What is the difference between indeterminate growth and determinate growth?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 35: Plant Structure, Growth, and Development
18.
Although plants generally show indeterminate growth, what are three examples of plant parts
that show determinate growth?
19.
Based on the length of their life cycle, plants are categorized into three groups. Explain what
each category means below, and provide an example.
Annuals
Biennials
Perennials
20.
Plants are capable of indeterminate growth because they have perpetually embryonic tissues
called
21.
.
Explain the following relationships.
Apical meristems and primary growth
Lateral meristems and secondary growth
Primary growth and secondary growth
Concept 35.3 Primary growth lengthens roots and shoots
22.
The figure below shows an image that is like a slide many students study in a mitosis lab and is
labeled for this lesson as the “Primary growth of a root.” Label the nine structures shown in the
figure: cortex, vascular cylinder, epidermis, apical meristem, root cap, root hair, zone of
differentiation, zone of elongation, and zone of cell division.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 35: Plant Structure, Growth, and Development
23.
Explain what events occur in the zone of cell division, zone of elongation, and zone of
differentiation.
24.
In most roots, the xylem and phloem is a solid cylinder of vascular tissue located in the center
of the root and called the stele. The figure below shows the stele of a dicot root. Label the
xylem, phloem, endodermis, and pericycle. Also define the two new terms as indicated.
Endodermis
Pericycle
25.
Why must new roots formed by the pericycle originate in the center of the root?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 35: Plant Structure, Growth, and Development
26.
From Figure 35.16, label shoot apical meristem, leaf primordia, young leaf, developing
vascular strand, and axillary bud meristems.
27.
What structure in this figure is responsible for primary growth?
28.
It is possible to tell a young eudicot from a monocot by the structure of the stem. In the
following figure, label the eudicot, monocot, epidermis, and vascular bundles.
29.
How is the arrangement of vascular bundles different in monocot and dicot stems?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 35: Plant Structure, Growth, and Development
30.
To understand the process of photosynthesis, students are expected to know leaf structure in
greater detail. Using Figure 35.18, label each structure just as shown in the text.
31.
What gas critical to photosynthesis enters the leaf through stoma?
32.
What is lost through the stoma that leads to transpiration?
33.
Is this a C3, C4, or CAM leaf?
Concept 35.4 Secondary growth adds girth to stems and roots in woody plants
34.
Primary growth arises from apical meristems and results in
stems, and leaves. Secondary growth arises from
cambium and results in increased
35.
of roots,
and
of roots and stems.
Explain what is produced by these structures.
Vascular cambium
Cork cambium
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
36.
Chapter 35: Plant Structure, Growth, and Development
Read the text that accompanies Figure 35.19 and then answer these questions.
a. What results in primary growth of the stem?
b. What cells are formed to the inside and the outside of the vascular cambium?
c. What is the difference in the formation of primary xylem and phloem versus secondary xylem
and phloem?
37.
What vascular tissue forms the bark, and what is the function of the bark?
38.
What tissues are included in the bark of a tree?
39.
On this figure, add these labels: cork cambium, cork, periderm, bark, growth ring, secondary
xylem, secondary phloem, and vascular cambium.
40.
Look back at the stem in Figure 35.19 and find the horizontal slits in the bark, known as
lenticels. You may have noticed lenticels on the young twigs of trees or shrubs. What is the
function of lenticels?
Concept 35.5 is omitted. These topics have not been included on recent AP Biology exams.
Testing Your Knowledge: Self-Quiz Answers
Now you should be ready to test your knowledge. Place your answers here:
1.
2.
3.
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4.
5.
6.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 36: Resource Acquisition & Transport in Vascular Plants
Name
Period
Chapter 36: Resource Acquisition and Transport in Vascular Plants
Concept 36.1 Land plants acquire resources both above and below ground
1.
Competition for light, water, and nutrients is intense among the land plants. Let’s look first at
adaptations to increase light capture. How do plants reduce self-shading?
2.
What triggers self-pruning?
3.
There are different leaf orientations, and each orientation affects light capture. Compare the
following as to the type of plant that has each orientation, and describe the advantage.
Orientation
Type of Plant
Advantage
vertical leaf orientation
horizontal leaf orientation
4.
What are mycorrhizae, and what is their role in resource acquisition?
Concept 36.2 Transport occurs by short-distance diffusion or active transport and long-distance
bulk flow
This section gives you a good review of the transport mechanisms you studied in Chapter 7. The
information in the next group of questions should be familiar to you. Also, many AP courses do AP
Laboratory 1, Diffusion and Osmosis, along with Chapter 7. It covers the concept of water potential, so
now might be a good time to review that lab activity.
5.
What is passive transport?
6.
What is active transport?
7.
What is the role of transport proteins?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 36: Resource Acquisition & Transport in Vascular Plants
8.
What are the most important plant cell transport proteins? How do they work?
9.
What is membrane potential? How can it be established?
10.
Explain cotransport.
11.
What is osmosis?
12.
Plant cells have a rigid cell wall, which adds another factor that affects osmosis: pressure.
Define water potential.
The equation for water potential is = s + p,, where is water potential, s is solute potential, and
p is the pressure potential. The understanding of this formula is an objective from Laboratory 1 in the
AP Laboratory book.
13.
By definition, what is the s of pure water?
14.
How does adding solutes to pure water affect water potential?
15.
The solute potential of a solution is therefore always
16.
What is pressure potential? Under what conditions will it decrease?
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. (negative or positive)
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 36: Resource Acquisition & Transport in Vascular Plants
17.
What is the water potential on the left side of tube A? Why?
18.
Is the water potential on the right side of tube A positive or negative?
19.
Explain, in terms of water potential, why the level of the liquid is higher on the right side of
tube A.
20.
In tube B, pressure is being applied on the right side. This is much like the pressure exerted by
the cell wall when a plant cell takes up water. Explain, in terms of water potential, why the
level of liquid is the same on both sides even though the two solutions are not isotonic to each
other.
21.
To summarize, water moves from regions of
water potential to regions of
water potential.
22.
Define these terms:
flaccid
turgid
plasmolysis
In the figure below, a plant cell that has an initial water potential of –0.7 MPa is placed into
two different conditions. Explain, in terms of water potential, what is happening in each case.
23.
a.
b.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 36: Resource Acquisition & Transport in Vascular Plants
24.
What are aquaporins?
25.
There are three major pathways of transport between plant cells. On the sketch, label and
explain:
transmembrane route
apoplast
symplast
26.
What is bulk flow?
Concept 36.3 Water and minerals are transported from roots to shoots
27. On the sketch, use colored pencils to trace the uptake of water and minerals from root hairs to the
xylem and phloem in a root, following a symplastic route and an apoplastic route. Then, label
each of the following elements: root hair, plasma membrane, plasmodesmata, stele, endodermis,
Casparian strip, symplastic route, and apoplastic route.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 36: Resource Acquisition & Transport in Vascular Plants
28.
What is the role of the Casparian strip?
29.
Write a short essay to explain the movement of water from the soil into the stele of the root,
using all the terms in question 27.
30.
What is transpiration?
31.
There are two mechanisms that pull water up through the plant, from roots to leaves. Explain
root pressure.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
32.
Chapter 36: Resource Acquisition & Transport in Vascular Plants
The second mechanism that pulls water up through the plant is transpiration-cohesion-tension.
Refer to this sketch in your text. Note that water is moving from a region of high water
potential to a region of lower water potential. The arrow on the left side of the figure shows this
gradient. Beginning from where you stopped in question 29, write an essay to explain the
movement of water from the roots to the leaves. Include each of these terms in your essay, and
label them on the figure: lower water potential, higher water potential, hydrogen bonding,
adhesion, cohesion, xylem tubes, and stomata.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 36: Resource Acquisition & Transport in Vascular Plants
Concept 36.4 Stomata help regulate the rate of transpiration
33.
Leaves generally have large surface areas and high surface-to-volume ratios. Give an advantage
and disadvantage of these traits.
advantage
disadvantage
34.
Plants lose 95% of their water through stomata! What controls the amount of water loss?
35.
On the sketches, label the guard cell, stomata, K+, and H2O. Explain why the stoma opens
when K+ accumulates in the guard cells.
36.
Three types of stimuli can cause guard cells to open. Name and explain how each one works.
Stimulus for Stomatal Opening and
Explanation
Closing
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 36: Resource Acquisition & Transport in Vascular Plants
37.
What plant hormone is produced in response to water deficiency?
38.
List four different physiological or morphological adaptations of xerophytes, and explain how
each of them reduces water loss.
Concept 36.5 Sugars are transported from leaves and other sources to sites of use or storage
39.
What is translocation?
40.
What is a sugar source, and what is a sugar sink? Give an example of each.
41.
What cell types transport the sugars?
42.
Explain the process of pressure flow by annotating the figure below. Refer to your text, and
divide this process into four steps.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
43.
Chapter 36: Resource Acquisition & Transport in Vascular Plants
Study Figure 36.21. How do aphids feed? When houseplants are infested with aphids, why is
there a sticky mess on the floor around them?
Concept 36.6 The symplast is highly dynamic
44.
Give two specific signals that move through the symplast, and describe the function of each
signal.
Testing Your Knowledge: Self-Quiz Answers
Now you should be ready to test your knowledge. Place your answers here:
1.
2.
3.
8.
9.
10.
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4.
5.
6.
7.
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Chapter 37: Soil and Plant Nutrition
AP Biology Reading Guide
Fred and Theresa Holtzclaw
Name
Period
Chapter 37: Soil and Plant Nutrition
Concept 37.2 Plants require essential elements to complete their life cycle
1.
What is an essential nutrient?
2.
What are the nine macronutrients? List them in order of relative abundance in plants. (You may
use atomic symbols.)
3.
What is a primary role of magnesium?
4.
What three macronutrients are most commonly deficient? You should notice that these are the
same three nutrients found in most fertilizers.
Concept 37.3 Plant nutrition often involves relationships with other organisms
5.
Which nutrient is most limiting to plant growth on a global scale?
6.
Plants have mutualistic relationships with bacteria that help make nitrogen more available.
Nitrogen-fixing bacteria such as Rhizobium are able to convert atmospheric nitrogen (N2),
which plants cannot use, to ammonia (NH3), which they can use. Review the nitrogen cycle by
labeling this diagram.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 37: Soil and Plant Nutrition
7.
Where is the nitrogen-fixing bacterium Rhizobium found?
8.
The principle of crop rotation employs alternation of a crop that depletes nitrogen with a
legume crop that fixes nitrogen. In the United States, this often means alternation of corn with
soybeans. Which of these two crops is the nitrogen depleter? The nitrogen fixer?
9.
How do mycorrhizae enhance plant nutrition?
10.
In many parts of the eastern United States, garlic mustard has become a serious pest. What is its
negative impact on native species, and how does it appear to do this?
11.
What is an epiphyte? Name three different plant types that are epiphytic.
12.
Dodder and Indian pipes are nongreen, nonphotosynthetic flowering plants. How do they
obtain nutrients?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
13.
Chapter 37: Soil and Plant Nutrition
Carnivorous plants such as the Venus flytrap and sundews are photosynthetic. Why, then, do
they capture insects?
Testing Your Knowledge: Self-Quiz Answers
Now you should be ready to test your knowledge. Place your answers here:
1.
2.
3.
8.
9.
10.
Copyright © 2010 Pearson Education, Inc.
4.
5.
6.
7.
-3-
AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 38: Angiosperm Reproduction and Biotechnology
Name
Period
Chapter 38: Angiosperm Reproduction and Biotechnology
Concept 38.1 Flowers, double fertilization, and fruits are unique features of the angiosperm life
cycle
This may be a good time for you to go back to Chapter 29 and review alternation of generation and the
terms associated with it. Figure 29.5 would be a good starting point. Then, review Concepts 30.1 and
30.3 on angiosperm life cycles. The angiosperm life cycle has three unique features, all of which start
with the letter F, a good memory aid: Flowers, Fruits, and double Fertilization. You will want to
remember these!
1.
On this sketch of a flower, label all floral parts and give the function of each. Label also the
stamen and carpel. Then, circle the flower parts that are essential for reproduction.
2.
What is another name for the microsporangia?
3.
Each microspore mother cell undergoes meiosis to form four haploid
4.
Each microspore undergoes mitosis to produce the male
5.
The male gametophyte is composed of only two cells. Name each cell, and tell what will come
from each of them.
Male Gametophyte Cells
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.
.
What does cell produce?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 38: Angiosperm Reproduction and Biotechnology
6.
What makes up a pollen grain?
7.
Label these parts: anther, pollen sac, microspores, male gametophyte, pollen grain, generative
cell, tube cell, megasporangium, megaspore mother cell, embryo sac, surviving megaspore,
polar nuclei, synergids, and egg.
8.
Meiosis in the female part of the plant produces four megaspores. How many survive?
9.
What occurs in pollination? Annotate
the figure to the right to explain pollination.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
10.
Chapter 38: Angiosperm Reproduction and Biotechnology
List five modes of pollination. For each mode, describe a feature of the flower that aids
pollination.
Mode
Feature of Flower
11.
Study the section in this concept under the heading “Double Fertilization” very carefully. Label
the figures below to show two sperm nuclei, pollen tube, female gametophyte, ovule, synergids,
polar nuclei, egg, and zygote. Describe what is happening in each sketch.
12.
Study the figure on the left above. You should be able to count a total of 7 cells and 8 nuclei.
Which of these are fertilized in double fertilization?
13.
When the polar nuclei are fertilized, what is formed?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 38: Angiosperm Reproduction and Biotechnology
14.
The chromosome number of endosperm is (a) haploid, (b) diploid, or (c) triploid.
15.
The chromosome number of the zygote is (a) haploid, (b) diploid, or (c) triploid.
16.
What is the role of the endosperm?
17.
After double fertilization, what does each ovule become?
18.
After double fertilization, what does each ovary become?
19.
Let’s compare the seeds of eudicots and monocots. How many cotyledons does each type have?
20.
What is the function of a seed coat?
21.
What part of the embryo plant emerges first?
22.
What are some mechanisms that maintain seed dormancy?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 38: Angiosperm Reproduction and Biotechnology
23.
Below are sketches of a bean seed and a corn seed. Label them to show: monocot, eudicot,
cotyledons, radicle, hypocotyl, epicotyl, seed coat, and endosperm. You may use the same term
several times.
24.
What is imbibition?
25.
To a botanist, a fruit is a ripe
pod is a fruit. A green pepper is a fruit.
26.
An important function of the fruit is to aid in dispersal. What are three primary methods of
dispersal?
. It does not have to be sweet! A pea
Concept 38.2 Flowering plants reproduce sexually, asexually, or both
27.
Asexual reproduction in plants is also known as vegetative propagation. Describe three
different types of asexual reproduction in plants.
28.
Why is it important for plants to have mechanisms to prevent self-fertilization?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
29.
Chapter 38: Angiosperm Reproduction and Biotechnology
What are two mechanisms to prevent self-fertilization?
Concept 38.3 Humans modify crops by breeding and genetic engineering
30.
Humans have used selective breeding to develop useful varieties since the dawn of agriculture.
Today, biotechnology has accelerated the introduction of desirable traits. List four genetically
modified plant species, and describe the advantage each species shows.
a.
b.
c.
d.
31.
Genetically modified organisms (GMOs) offer great promise but are also controversial. What
are three of the possible risks?
a.
b.
c.
Testing Your Knowledge: Self-Quiz Answers
Now you should be ready to test your knowledge. Place your answers here:
1.
2.
3.
8.
9.
10.
Copyright © 2010 Pearson Education, Inc.
4.
5.
6.
7.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 39: Plant Responses to Internal and External Signals
Name
Period
Chapter 39: Plant Responses to Internal and External Signals
Concept 39.1 Signal transduction pathways link signal reception to response
This concept brings together the general ideas on cell communication from Chapter 11 with specific
examples of signal transduction in plants. As with animals, plants have receptors that trigger signal
transduction pathways when activated. Let’s begin with a review of three steps in signal transduction.
Step 1: Reception. Cell signals are detected by receptors that undergo changes in shape in response
to a specific stimulus.
Step 2: Transduction. Transduction is a multistep pathway that amplifies the signal. This effect
allows a small number of signal molecules to produce a large cellular response.
Step 3: Response. Cellular response is primarily accomplished by two mechanisms:
a. increasing or decreasing mRNA production
b. activating existing enzyme molecules
1.
Have you ever seen a shriveled potato sending out skinny, pale sprouts? What is this called?
2.
If you move the potato into the light, the sprout will respond by forming short, sturdy stems and
broad, green leaves. What is this response to light called?
3.
The figure below gives a specific example of a signal transduction in plants for the greening or
de-etiolation response described above. Label these parts of the figure: reception, transduction,
response, phytochrome, signal, Ca2+ channel, second messenger (cGMP), protein kinase,
transcription factor, and DNA.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 39: Plant Responses to Internal and External Signals
4.
Return to the figure and explain how the light signal causes the greening response. You may
choose to number the steps, as shown in the figure in your text.
5.
What are the two second messengers in this pathway?
Concept 39.2 Plant hormones help coordinate growth, development, and responses to stimuli
6.
Both plants and animals have hormones. The definition of a hormone has three parts. What are
they?
7.
Plant physiologists think the term hormone as defined above doesn’t quite fit plants. What term
do they use instead?
8.
What is a tropism?
9.
The sketch below describes early experiments on phototropism conducted by Charles and
Francis Darwin. What can be concluded from these experiments?
CONCLUSION
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
10.
Chapter 39: Plant Responses to Internal and External Signals
Here is a sketch of the Boysen-Jensen experiment. What conclusions can be drawn from it?
CONCLUSION
11.
Boysen-Jensen’s work was published in 1913. In 1926, Frits Went modified the experiment
using agar cubes with a chemical from the coleoptile tips. Explain the results of this
experiment.
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 39: Plant Responses to Internal and External Signals
12.
What name did Went give to this chemical messenger? What was its chemical structure found
to be?
13.
In jest, we tell our students that when in doubt about which plant hormone causes which plant
response, just answer auxin. Auxin has so many functions, this answer often works. List and
describe four functions of auxin.
Auxin Functions
14.
Did you catch the discussion of auxins as herbicides? Perhaps you have used Weed-B-Gone to
kill dandelions in your lawn. Explain how this product kills dandelions without killing the
grass.
15.
How did cytokinins get their name?
16.
List and describe three functions of cytokinins.
Cytokinin Functions
17.
Description
Description
Gibberellins occur naturally in plants, and like the previous two hormones, they have several
effects. Describe three of them.
Gibberellin Functions
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 39: Plant Responses to Internal and External Signals
18.
Abscisic acid (ABA) is misnamed. Why?
19.
Describe three effects of abscisic acid.
Abscisic Acid Functions
Description
20.
Ethylene is the only hormone in our group that is a gas. Under what conditions is ethylene
produced?
21.
The effects of ethylene are many and varied. Describe them here.
Ethylene Functions
22.
Description
You have just finished a very complex look at plant hormones. Let’s try to summarize it by
completing the following chart.
Hormone
Action
leaf abscission
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 39: Plant Responses to Internal and External Signals
breaking seed dormancy
maintaining apical dominance
making internodes of grape bunches elongate to obtain larger fruit
gravitropism
drought tolerance
senescence
phototropism
cell elongation
increased cell division
Concept 39.3 Responses to light are critical for plant success
23.
Researchers have determined that plants have two major classes of light receptors. List each
class.
24.
What wavelengths of light are absorbed by phytochromes?
25.
What are three different responses initiated by blue light?
26.
Read carefully the discussion of phytochromes and how they work. Pay attention to the two
types of red light. What is the wavelength of red light?
Of far-red
light?
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AP Biology Reading Guide
Fred and Theresa Holtzclaw
Chapter 39: Plant Responses to Internal and External Signals
27.
Phytochromes are photoreceptors that have two isomer forms, Pr and Pfr. Sketch the conversion
of Pr to Pfr on this figure. Label all of the boxes, and also chromophore, phytochrome.
28.
What is the active form of phytochrome, Pr or Pfr?
29.
Look again at the effect of light exposure on lettuce seed germination. What determines the
seed’s response?
30.
To make sense of all this, you will want to read carefully the “Phytochromes and Shade
Avoidance” section. Which type of red light is more common in a shaded area? Why?
31.
What is a circadian rhythm? Give one plant example and one human example.
32.
What is the photoperiod?
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Fred and Theresa Holtzclaw
33.
Chapter 39: Plant Responses to Internal and External Signals
Plants detect photoperiod, and in many species it affects their time of flowering. Explain each
of the following, and give an example of a plant that is in the group.
short-day plant
long-day plant
day-neutral plant
34.
The plant in the sketch below is a short-day plant. Label R, FR, and critical dark period. For
each line, explain why flowering occurs or does not occur.
35.
What is florigen?
Concept 39.4 Plants respond to a wide variety of stimuli other than light
36.
What is gravitropism? How may a plant detect gravity?
37.
What is thigmotropism? How is it adaptive?
Copyright © 2010 Pearson Education, Inc.
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AP Biology Reading Guide
Chapter 39: Plant Responses to Internal and External Signals
Fred and Theresa Holtzclaw
38.
Describe an example of a rapid leaf movement. What do these action potentials
resemble?
39.
List six different ways in which a plant responds to water deficit.
40.
Select any other stress situation besides water deficit, and explain plant mechanisms
for dealing with this.
Concept 39.5 Plants respond to attacks by herbivores and pathogens
41.
What are the two ways in which a plants combat excess herbivory?
42.
Describe two examples of a plant producing chemicals to deal with herbivory.
Testing Your Knowledge: Self-Quiz Answers
Now you should be ready to test your knowledge. Place your answers here:
1.
7.
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8.
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9.
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10.
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