The Evolution of Plants Flashcards
(125 cards)
1
Q
What was needed for photosynthetic plants to move into land?
A
The evolution of chloroplasts
2
Q
What is the Primary endosymbiosis derived from?
A
Plantae
3
Q
First Clades to branch off after primary endosymbiosis?
A
Aquatic (algae)
4
Q
Three key characteristics of the evolution of land plants:
A
Protected embryos, vascular tissues, and seeds
5
Q
Ancestor of Plantae
A
Unicellular, similar to modern glaucophytes
6
Q
Chloroplasts retain:
A
Peptidoglycan between membranes (as cyanobacteria)
7
Q
Key synapomorphy of land plants:
A
Embryo that is protected by tissue.
8
Q
Land plants are also called:
A
Embryophytes
9
Q
Ten major clades:
A
Liverworts
Mosses
Hornworts
Lycophytes
10
Q
Vascular plants
A
Tracheophytes, called tracheids (7 clades)
11
Q
Nonvascular plants:
A
Some have conduction cells, but no tracheids
12
Q
Classifications of Land Plants:
A
- Nonvascular Land Plants
- Vascular Plants
- Seed Plants
13
Q
Land Plants develop
A
- Transport systems
- Structural support
- New ways to disperse gametes and progeny.
14
Q
Adaptations of Land Plants
A
-Cuticle
-Stomata
-Gametangia
-Embryos
Pigments and Spores
15
Q
Cuticle
A
Waxy coating that slows water loss
16
Q
Stomata
A
Closable opening that regulate gas exchange and water loss
17
Q
Gametagia
A
Organs that enclose gametes and prevent them from drying out
18
Q
Embryos
A
Young plants contained within a protective structure
19
Q
Pigments
A
Protect against UV radiation
20
Q
Spores
A
With thick walls containing a polymer that prevents drying and resists decay
21
Q
Land plants have alternation of generations:
A
- Multicellular diploid stage and multicellular haploid stage
- Gametes produce by mitosis
- Spores produced by meiosis
- Spores develop haploid organisms.
22
Q
Diploid zygote:
A
Develops by mitosis and cytokinesis
23
Q
Multicelluar diploid plant is called :
A
sporophyte
24
Q
Spores develop into
A
Gametophyte, multicellular haploid plant
25
Gametophyte produces
Haploid gametes
26
Fusion of gametes produces:
Diploid Zygote, which then develops into sporophyte
27
Nonvascular Plants
Liverworts, mosses, hornworts
28
Charateristics of nonvascular plants:
- Live in moist habitats
- Small
- No vascular system to transport water
29
Liverworts
- Green
- Sporophyte attached to gametophyte
- Can reproduce asexually or sexually
30
Mosses
- Stomata-important for gas exchange and water retention
| - Cells called hydroids which die and leave a channel through water can move.
31
Hornworts:
- Sporophytes look like small horns.
- Cells have one chloroplast
- Sporophyte
- Symbiotic relationships with cyanobacteria and fix nitrogen.
32
Nonvasular plants, gametophyte is:
Photosynthetic
33
What does the sporophyte depend on:
Gametophyte
34
Where are Gametes produced:
Gametangia (antheridia and archegonia)
35
Sperm must:
Swim or be splashed by water to reach the egg
36
What must be present for reproduction
Water
37
Vascular system consists:
Tissues for transport of water and materials
38
How did evolution help Vascular tissue:
Allowed plants to spread to new environments and diversify
39
Xylem conducts:
Water and minerals
40
Phloem conducts:
Products of photosynthesis
41
Tracheid:
Evolved in sporophytes and critical for invasion of land.
42
Tracheid includes;
Transport, the lignin provides support and allowing taller growth, which means more sunlight and disperse spores.
43
Vascular plants also developed:
Branching
44
What does branching do:
Spore production
45
Sporophyte of a vascular plant
Independent of the gametophyte
46
Invasion of land by vascular plants:
Made environment more hospitable to animals
47
What moved to land after vascular plants
Arthropods, vertebrates, and animals
48
When did trees appeared:
Devonian
49
When did trees dominate:
Carboniferous, when huge club mosses, horsetails, and tree ferns
50
What transformed into coal
Buried plant material
51
What happend in the Permian:
Gymnosperms replaced loycophyte - fern forests
52
Rhyniophytes
Earliest vascular plants
53
Rhyniophytes include:
No roots, anchored in soil by rhizomes with rhizoids ( ferns today) and dichotomous
54
Lycophytes
Club mosses, spike mosses and quilworts
55
Lycophytes include:
Microphylls and Strobili
56
Monilophytes
Horsetails and ferns. All have different main stem and side branches
57
Horsetails
Independent sporophyte and gametophyte
58
When did ferns appeared:
Devonian period, terrestrial
59
How long can sporophyte live:
Hundreds of years
60
Why is water so important:
Needed to transport of male gametes to female gametes so ferns are inhabit shaded, moist woodlands and swamps.
61
Sporangia
Borne on a stalk in clusters called sori
62
Microphylls evolved from:
Sterile sporangia
63
How did
| Megaphylls of monilophytes arise:
Photosynthetic tissue developed between branch pairs that were left behind as dominant branches overtopped them.
64
Euphyllophytes
Clade consisting of monilophytes
65
A synapomorphy of euphyllophytes
Overtopping growth
66
Euphyllophytes lead to
Megaphylls
67
Seed plants
Provide lasting dormant stage for the embryo. Can also be dormant for many years.
68
Trend in plant evolution:
Sporophyte became less dependent and gametophyte became smaller.
69
Seed plants evolved:
Independence from water for getting the sperm to the egg.
70
Male gametophyte
Pollen grain
71
Sporopollenin
Prevents drying and chemical damage
72
Megaspores develop:
Into female gametophytes
73
What are megagametophytes are dependent:
On sporophyte for food and water
74
Megagametophytes develop in:
Ovule, which later became the seed
75
Pollination
Arrival of a pollen grain near a female gametophyte
76
Pollen tube
Grows the grain and digests its way toward megagametophyte.
77
Diploid Zygote:
Divides to form an embryonic sporophyte, enters a dormant stage
78
Seed contains tissues from three generation:
A seed coat, Haploid tissue from the female gametophyte provides nutrients, and embryo is the new diploid Sporophyte.
79
Many seeds remain:
Viable for long periods
80
Seed coat:
Protects from drying, potential predators and other damage.
81
What do the adaptiations of seeds to help:
Aid in dispersal
82
Where does the embryo get nutirients:
Stored in the seed
83
Secondary growth:
Increasing diameter of roots and stems by growth of xylem
84
Older wood:
Becomes clogged with resins but provide support and allows plants to grow.
85
Gymnosperms
Seed plants that do not form flowers or fruits
86
What is not protected in gymnosperms:
Ovules and seeds.
87
Gymnosperms have:
Tracheids as water conducting and support.
88
Four groups of gymnosperms:
Cycads, Gingkos, Gnetophytes, Conifers
89
Cycads
Tropical, earliest diverging clade
90
Gingkos
Common in Mesozoic, today only species: Gingko biloba
91
Gnetophytes
Some characteristics similar to angiosperms; Welwitschia
92
Conifers
Cone-bearing plants
93
Conifers include:
Dominate forests at high latitudes and high elevations
94
Cones contain:
Megastrobilus and Microstrobilus
95
Megastrobilus
Female cone
96
Microstrobilus
Male pollen
97
What transports pollen grains
Wind
98
What are the most exposed:
Conifer Ovules
99
Angiosperms
Reproductive organs in flowers; seeds are enclosed in fruits
100
Carpel
Ovules and seeds enclosed in modified leaf
101
What is very reduced:
Female gametophyte
102
Xylem of amgiosperms
Vessel elements- water transporting cells
103
Fibers
Structural support
104
Pholem
Companion cells
105
Synapomorphies of the angiosperms
Germination of pollen on a stigma, Double fertilization, Endosperm
106
Infloresence
Group of flowers
107
Stamens bear
Male microsporangia
108
Stamen is composed
Filament and anther
109
Carpels bear
Megasporangia
110
Carpels contain:
Ovary, style and stigma
111
Imperfect flowers
two flowers types male and female
112
Monoecious
Male and female flowers occur on the same plant
113
Dioecious
Male and female flowers are produced on different plants
114
Evolution of flowers
Earliest diverging clades have many tepals, carpels and stamens
115
Most angiosperms are pollinated by:
Animals
116
Double fetilization:
Each pollen contains two male gametes: one combines with egg. The other combines with two other haploid nuclei to form a triploid cell, triploid cells give rise to endosperm
117
Zygote develops:
Into an embryo with embryonic axis and cotyledons (seed leaves)
118
Fruits:
Develop from ovaries after fertilization, protect seeds and aid in dispersal
119
Single fruit
Develops from a single carpel or fused by carpels ( plum or peach)
120
Aggregate fruit
Develops from several separate carpels of a single flower (raspberry)
121
Multiple fruit
Forms from a flower cluster, inflorescence (pineapples and figs)
122
Accessory fruit
Develop from other parts in addition to the carpel (apples, pears, strawberries)
123
Amborella (magnoliids)
Sister group of all other flowering plants
124
1. Angiosperm clades:
Monocots (1 cotyledon) grasses, cattails, ilies, orchids and palms.
125
2. Angiosperm clades:
Eudicots (2 cotyledons) majority of familiar seed plants
