Lesson 6- The colonization of Land by Plants Flashcards
• summarize the plant adaptations to life on land • elaborate on the alternation of generations among seedless nonvascular and vascular plants • trace the evolution of seedless nonvascular and vascular plants • discuss the economic and ecological importance of mosses and other seedless vascular plants
1
Q
These two evidences suggest that thin coatings of cyanobacteria and protists existed on land 1.2 billion years ago.
A
Geochemical analysis and fossil evidence
2
Q
The terrestrial surface was lifeless for more than how many years of earth’s early history?
A
3 billion years
3
Q
In what timescale do Cyanobacteria likely exist on land?
A
1.2 BYA
4
Q
At around what timescale did small plants, fungi, and animals emerge on land?
A
500 MYA
5
Q
Since colonizing the land, plants have diversified into roughly how many living species?
A
290,000
6
Q
Land plants do not include what photosynthetic microorganisms?
A
Photosynthetic protists (algae)
7
Q
Plants supply ______ and are the ultimate source of most food eaten by land animals
A
oxygen
8
Q
These are a group of algae which are the closest relatives of land plants.
A
Charophytes
9
Q
The ancestor of land plants was most likely shared with a group of green algae known as what?
A
Charophytes
10
Q
Many characteristics of land plants also appear in various algal clades, mainly what?
A
algae
11
Q
what are the four key traits that land plants and charophytes share?
A
- Rings of cellulose-synthesizing complexes.
- Peroxisome have enzymes.
3.Structure of Flagellated Sperm - Formation of Phragmoplast
12
Q
What are the two comparisons that point to charophytes as the closest living relatives of land plants?
A
Nuclear and chloroplast genes.
13
Q
This is an adaptation that enabled the move to land. Found in charophytes which has a layer of durable polymer that prevent exposed zygotes from drying out.
A
Sporopollenin
14
Q
The movement onto land by charophyte ancestors was possible due to what factors?
A
- Unfiltered Sunlight
- More plentiful CO2
- Nutrient-rich soil
- few herbivores and pathogens
15
Q
What are some challenges faced by plants?
A
Scarcity of water and lack of structural support.
16
Q
An adaptation that enabled the move to the land. Which facilitated survival, it may have opened the way to its colonization by plants.
A
Accumulation of traits
17
Q
These two evidences suggest that thin coatings of cyanobacteria and protists existed on land 1.2 billion years ago.
A
Geochemical analysis and fossil evidence
18
Q
Until this debate about the boundaries of the plant kingdom, plants are referred to as what?
A
embryophytes
19
Q
This is a a mutualistic relationship between plants and fungi
A
Mycorrhizal symbiosis
20
Q
This evidence suggests that the first land plants were already involved in mycorrhizal symbiosis
A
Extensive fossil evidence
21
Q
“Lower” plants, such as the mosses, liverworts, ferns, and horsetails, still have this root like structure and lack this feature
A
rhizomes;well-developed vasculature
22
Q
This is the same sort of structure that was found in fossilized plants some 400 million years ago.
A
arbuscule
23
Q
In this timescale, the algal ancestors of plants may have carpeted moist fringes of lakes and coastal salt marshes
A
More than 500 MYA
24
Q
This is a group that constitutes both plants and green algae
A
charophytes
25
These organisms are thought to have evolved from a common ancestor
charophytes
26
Do charophytes have simple unicellular bodies?
No, they have complex multicellular bodies
27
Are charophytes photosynthetic prokaryotes?
No, they are photosynthetic eukaryotes.
28
Do algae have tissues like that of plants?
No
29
What are the three opportunities that allowed adaptations of plants for life on land?
1. Unlimited Solar Energy
2. Abundant CO2
3. Initially, few pathogens and herbivores.
30
List 4 difficulties of plants on land.
– maintain moisture inside their cells to keep them from drying out
– support their body in a non-buoyant medium
– reproduce and disperse offspring without water
– obtain resources from soil and air
31
List 6 features that algae have unlike land plants
1. Generally have no rigid tissues
2. Are supported by the surrounding water
3. Obtain CO2 and minerals directly from the water surrounding the entire algal body
4. Receive light and perform photosynthesis over most of their body
5. Use flagellated sperm that swim to fertilize an egg
6. Disperse offspring with water
32
Do Land plants maintain moisture in their cells? How?
Yes, because of stomata
33
These are growth-producing regions of cell division.
Apical Meristem
34
In many land plants, water and minerals move up from roots to stems and leaves using these types of tissues.
vascular tissues
35
What are the two vascular tissues?
Xylem and Phloem
36
What is the xylem made of, and state one function.
* consists of dead cells
* transports water and minerals
36
What is phloem made of and state one function.
It consists of living cells.
It conveys sugars.
36
True or False. In all plants, the gametes and embryos must be kept moist.
True
37
T or F: In algae, the zygote develops into an embryo while attached to and nourished by the parent plant.
False: In land plants
38
What is the life cycle involved in the alternation of generation in land plants?
Haploid Generation which produces eggs and sperm
Diploid Generation which produces spores
39
Spores of land plants are protected within structures called the what?
sporangia
40
In pines and flowering plants, what are these structures that contain the sperm-producing cells?
pollen grains
41
Sate the four predecessors of the ancestral algae. Recognize which is viridiplantae, streptophyta, and plantae
1. Red Algae
2. Chlorophytes
3. Charophytes
4. Embryophytes
42
List four key traits that appear in nearly all
land plants but are absent in the
charophytes
1. Alternation of generations and multicellular, dependent embryos
2. Walled spores produced in sporangia
3. Multicellular gametangia
4. Apical meristems
43
In the Alternation of Generations and Multicellular, Dependent Embryos. What is the ploidy of the gametophyte and the specific process of division?
haploid; mitosis
44
In the sporophyte generation of the land plants. What is the ploidy of the sporophyte and what is the type of cell division used to produce spores?
Diploid sporophyte; haploid spores by meiosis
45
In Alternation of Generations and Multicellular, Dependent Embryos. Where is the diploid embryo retained?
Tissue of the female gametophyte
46
In Alternation of Generations and Multicellular, Dependent Embryos. Nutrients are transferred from parent to embryo through what?
placental transfer cells
47
Why are land plants referred to as embryophytes?
48
Why are land plants referred to as embryophytes?
Because of their dependency on the embryo on the parent.
49
The sporophyte produces spores in organs known as what?
sporangia
50
Diploid cells known as ________ undergo meiosis to generate _________
sporocytes; haploid spores
51
Spore walls contain this substance, which makes them resistant to harsh environments
sporopollenin
52
This is referred to as the female gametangia
archegonia
53
A pear-shaped organ that produces a single non-motile egg retained within the bulbous part of the organ.
Archegonia
54
This is referred to as the male gametangium
Antheridium
55
In many groups of present-day plants, the sperm
possess flagella and swim to the eggs through
water droplets or a film of water.
Antheridium
56
In land plants, eggs are fertilized within what structure? It is where the zygote develops into an embryo.
archegonium
57
T or F: Seed plants' Gametophytes are so small that the archegonia and antheridia have been lost in many lineages.
true
58
These are referred to are specialized zones of growth found at the tips of plants.
Apical Meristem
59
This is a group of cells, up to 1,000 in number, in the form of a hemisphere, with the flat face toward the root tip of vascular plants.
quiscent center
60
This is a waxy covering of the epidermis.
Cuticle
61
Referred to as the symbiotic associations between fungi and land plants that may have helped plants without true roots to obtain nutrients
Mycorrhizae
62
These are substances that deter herbivores and parasites.
Secondary compounds
63
In The Origin and Diversification of Plants, Fossil evidence indicates that plants were on land for
At least how many years?
475MYA
64
What are these two evidences that have
been extracted from 475-million-year-old rocks
Fossilized spores and tissues
65
True or False: Predecessor species gave rise to a vast diversity of modern plants
False: Ancestral
66
True or False: Plant unity reflects the evolutionary history of the plant kingdom
False: diversity
67
Land plants can be informally grouped based
on the presence or absence of this tissue.
vascular tissue
68
Most plants have vascular tissue; these
constitute the what group of plants?
vascular plants
69
Nonvascular plants are commonly known as
what?
bryophytes
70
Bryophytes are not a monophyletic group; their relationships to each other and to vascular plants are unresolved. T or F
True
71
Seedless vascular plants can be divided into
two clades; which are?
1. Lycophytes
2. Pterophytes
72
Give examples of lycophytes.
Club mosses and their relatives
73
Give examples of pterophytes
ferns and fern allies
74
Seedless vascular plants are ______, and are of the same grade or level of biological organization
paraphyletic
75
Mosses and other nonvascular plants have life cycles dominated by what multicellular phase?
gametophyte
76
Bryophytes are represented today by three phyla of small herbaceous (nonwoody) plants. Which are?
1. Liverworts
2. Hornworts
3. Mosses
77
This term refers to all nonvascular plants
bryophytes
78
In the Bryophyte Gametophytes; gametophytes are smaller and shorter-living than sporophytes
False: larger;longer-living
79
In Bryophyte Gametophytes: Sporophytes are typically present most of the time.
false; only part of the time.
80
What are the two compositions of the gametophyte?
1. Protonema
2. Gametophore
81
This structure anchor gametophytes to a substrate
Rhizoids
82
These are structures that produces flagellated sperm in antheridia and an egg in each archegonium
Mature gametophytes
83
T or F: Sperm SWIMS through a film of water to reach and fertilize the egg
True
84
What are these structures that grow out of the archegonia and are the smallest and simplest sporophytes of all extant plant groups
bryophyte sporophytes
85
What are the three parts of the bryophyte sporophyte?
1. foot
2. seta
3. sporangium
86
Sporangium discharges spored through what structure?
peristome
87
Hornwort and moss sporophytes possess this structure for gas exchange
stomata
88
State the Ecological and Economic importance of moss.
* capable of inhabiting diverse and sometimes extreme environments, but are especially common in moist forests and wetlands
* Some mosses might help retain nitrogen in the soil
89
They form extensive deposits of partially decayed organic material known as peat.
Sphagnum or peat moss
90
This is sourced from sphagnum moss that can be used as a source of fuel.
peat
91
T or F: Sphagnum an important global reservoir of
sulfur
False: carbon
92
T or F: Overharvesting of Sphagnum and/or a drop in water level in peatlands could release stored CO2
true
93
These are prevalent vegetation during the first 100
million years of plant evolution.
Bryophytes and bryophyte-like plants
94
When did
94
What period did vascular plants began to diversify
Devonian and Carboniferous periods
95
What allowed these plants to grow tall
vascular tissues
96
What types of plants have flagellated sperm and are usually restricted to moist environments
Seedless vascular plants
97
Fossils of the forerunners of vascular plants
date back to how long?
about 425 million years
98
Living vascular plants are characterized by:
1. Life cycles with dominant sporophytes
2. Vascular tissues called xylem and phloem
3. Well-developed roots and leaves
99
In contrast with charophytes, sporophytes of seedless vascular plants are larger significant generation, as in familiar ferns.
False, bryophytes
100
These are tiny plants that grow on or below the soil surface
gametophytes
101
Roots may have evolved from what structures?
subterranean stems
102
Leaves are categorized into two types; which are?
Microphylls and Megaphylls
103
These are leaves with single veins
microphylls
104
These are leaves with a highly branched vascular system
megaphylls
105
According to one model of evolution, microphylls
evolved as what?
outgrowths of stems
106
These are modified leaves with
sporangia
Sporophylls
107
These are clusters of sporangia on the undersides of sporophylls
sori
108
These are cone-like structures
formed from groups of sporophylls.
Strobilli
109
True or False: Most seedless vascular plants are
heterosporous
false, homosporous
110
T or F: All seed plants and some seedless vascular plants are homosporous
false, heterosporous
111
Heterosporous species produce this type of spore structure
megaspores
112
Classification of Seedless Vascular. What are the two phyla of seedless vascular plants?
Phylum Lycophyta and Phylum Pterophyta
113
T or F: Club mosses and spike mosses have
vascular tissues.
True
114
T or F: Club mosses, spike moss, and quillworts are not true mosses
True
115
T or F; Phylum Pterophyta are the most diverse seedless vascular plants, with more than 12,000 species
True
116
In what period when horsetail were diverse, but are now restricted to the genus Equisetum
Carboniferous period
117
These ferns resemble ancestral vascular plants but are closely related to modern ferns
Whisk ferns
118
In what period did ancestors of modern lycophytes,
horsetails and ferns grew to great heights forming the first forests
Devonian and Carboniferous Periods
119
What period when there is Increased growth and photosynthesis removed CO2 from the atmosphere
Carboniferous period
120
Decaying plants of these Carboniferous forests eventually became ____
coal
121
This is an embryo including nutrients surrounded by a protective coat
seed
122
Seed plants form a clade and can be divided
into further clades:
Gymnosperms, the “naked seed” plants, including the conifers
Angiosperms, the flowering plants
123
Differentiate seeds of Gymnosperms and Angiosperms
Gymnosperm seeds are exposed on sporophylls that form cones.
Seeds are enclosed within the fruit, which is a mature ovary
124
In addition to seeds, the following are
common to all seed plants. Which are?
– Reduced gametophytes
– Heterospory
– Ovules
– Pollen
125
Advantages of Reduced Gametophytes
The gametophytes of seed plants develop within the walls of spores that are retained within tissues of the parent sporophyte
126
Heterospory of seedless and seed plants, respectively.
homosporous and heterosporous
127
1. Megasporangia produce _____
that give rise to _____ gametophytes
2. Microsporangia produce ____
that give rise to ______ gametophytes
1. megaspores; female
2. microspores; male
128
State 3 parts of an ovule
– megasporangium
– megaspore
– one or more protective integuments
129
How many integuments in gymnosperms and angiosperms, respectively?
one integument; usually two integuments
130
Microspores develop into _____, which contain the male gametophytes
pollen grains
131
This is the transfer of pollen to the part of a seed plant containing the ovules
pollination
132
This eliminates the need for a film of water and can be dispersed at great distances by air or animals
pollen
133
If a pollen grain germinates, it gives rise to a _____ that discharges sperm into the female gametophyte within the ovule
pollen tube
134
Seeds provide some evolutionary advantages over spores. State Three.
1. They may remain dormant for days to years, until conditions are favorable for germination.
2. Seeds have a supply of stored food.
3. They may be transported to long distances by wind or animals.
135
What period did gymnosperms dominate the terrestrial ecosystem?
Mesozoic era
136
Angiosperms began to replace gymnosperms near the end of the what era?
mesozoic era
137
What period did progymnosperms begin to acquire some adaptations that characterized seed pla nts
Late Devonian period
138
Considered the earliest seed plant known to
date. What period did it come from?
Elkinsia polymorpha
139
A structure that functions to enclose and protect the ovules.
Cupules
140
This is the the female gametophyte and associated tissues which develop into a seed upon fertilization
Ovules
141
Four phyla of gymnosperms
1. cycads
2. Ginkophyta
3. Gnetophyta
4. Conifers
142
These phylum thrived during the Mesozoic, but
relatively few species exist today
cycadophyta
143
This phyla have large cones and palm-like
leaves
cycads or cycadophyta
144
This phylum consists of a single living species. They have a high tolerance for air pollution. Also, a famous ornamental tree
Ginkophyta
145
This phylum comprises three genera. The species vary in appearance and some are tropical whereas others live in deserts
Gnetophyta
146
A pine tree is a sporophyte or gametophyte?
sporophyte
147
In gymnosperm, cycle: What is the dominant generation?
sporophyte generation
148
All angiosperms are classified in a
single phylum: which is?
Anthophyta
149
Two key adaptations of Angiosperms
Flowers and Fruits
150
What is the site of pollination and fertilization in angiosperms?
flowers.
151
State the four parts of a flower.
– Sepals
– Petals
– Stamens
– Carpels
152
In angiosperms, state the key events in typical life cycle.
1. Meiosis in the anthers produces haploid spores that form the male gametophyte (pollen grains).
2. Meiosis in the ovule produces a haploid spore that forms the few cells of the female gametophyte, one of which becomes the egg.
3. Pollination occurs when a pollen grain lands on the stigma. A pollen tube grows from the pollen grain to the ovule.
4. The tube carries a sperm that fertilizes the egg to form a zygote.
152
In angiosperms, state the key events in typical life cycle.
1. Meiosis in the anthers produces haploid spores that form the male gametophyte (pollen grains).
2. Meiosis in the ovule produces a haploid spore that forms the few cells of the female gametophyte, one of which becomes the egg.
3. Pollination occurs when a pollen grain lands on the stigma. A pollen tube grows from the pollen grain to the ovule.
4. The tube carries a sperm that fertilizes the egg to form a zygote.
5. Each ovule develops into a seed consisting
of an embryo (a new sporophyte) surrounded
by a food supply and a seed coat derived from the integuments.
6. While the seeds develop, the ovary’s wall
thickens, forming the fruit that encloses the
seeds.
7. When conditions are favorable, a seed
germinates.
153
This consists of a mature ovary but can also include other flower parts
Fruits
154
The function of fruit.
Protect seeds and seed dispersal.
155
T or F: Fruits are mature and ripened ovules of flowers
False; ovaries
156
Angiosperm Diversity comprises more than _____ living species
250,000
157
DNA studies suggest that monocots form a clade, but dicots are ______
paraphyletic
158
T or F: The clade eudicot (“true” dicots) includes most dicots
True
159
This group include the flowering plants belonging
to the oldest lineages.
Basal angiosperms
160
This angiosperm group shares some traits with basal angiosperms, however, evolved later
Magnoliids
161
State the types of cotyledonous groups
Monocots
Eudicots
Dicots
162
T or F: Pollination by animals has influencedangiosperm evolution.
True
163
About 90% of angiosperms use animals
to transfer their pollen. Give four examples
– Birds are usually attracted by colorful flowers, often red, but without scent.
– Most beetles are attracted by fruity odors but are indifferent to color.
– Night-flying bats and moths are usually attracted by large, highly scented flowers that are often white.
– Wind-pollinated flowers typically produce large amounts of pollen.
164
Fossil evidence indicates that flowering plants first appeared in the Lower Cretaceous era about _____
125 MYA
165
T or F: Animals influence the evolution of plants and vice versa
True
166
T or F: Clades with bilaterally symmetrical flowers have more species than those with radially symmetrical flowers
True
167
T or F: Human welfare depends greatly on non-seed plants
False: seed plants
168
True or False: Most of our food comes from Gymnosperms
False: Angiosperms
169
State two examples of how animals influence the evolution of plants and vice versa
– animal herbivory selects for plant defenses
– interactions between pollinators and flowering plants select for mutually beneficial adaptations
170
This hypothesis proposed that the early ancestors of angiosperms were shrubs based from molecular evidence.
woody magnoliid hypothesis
171
This fossil evidence recovered from Jurassic
geological material has been attributed to
angiosperms.
Fossilized pollen
172
State at least three importance of seed plants in terms of products,
* Most of our food comes from angiosperms
* Six crops (wheat, rice, maize, potatoes, cassava, and sweet potatoes) yield 80% of the calories consumed by humans
* Modern crops are products of relatively recent genetic change resulting from artificial selection
* Many seed plants provide wood
* Secondary compounds of seed plants are used in medicines
