Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIOLOGY 1030 > Plant diversity > Flashcards

Plant diversity Flashcards

1
Q

When did Cyanobacteria emerge? When did the others join?

A

1.2 billion years ago

Other fungi, algae, “plants” joined ~700 million years ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is the earliest evidence of trees?

A

Earliest evidence of trees in Megouasag (Micmac for “red cliffs”)
Archaeopteris is a historical tree
Fossil beds are ~380 million years old
Development of lignin allowed for super rigid cell walls to support upward grow
Had fern-like leaves -> surface area allowed more efficient photosynthesis to compete with early plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are plants apart of?

A

are part of Archaeplastida

Unicellular, multicellular and/or colonial members

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 2 main clades of Archaeplastida ?

A 
Green algae (paraphyletic because 2 main groups charophytes and other one)  
Red algae (monophyletic) -> have a holdfast, stipe(stem), blade (leaf)

Use of photosynthetic pigments allows for the adaptation to different environments and also identifies members

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What did plants evolve from

A

Plants evolved from green algae

Green algae called charophytes are the closest relatives of plants.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which traits in algae and plants?

A

Some of these traits were acquired independently and tell an incomplete story with respect to the origin of plants
Multicellularity
Photosynthetic pigments (i.e. chlorophylls)
Cell walls composed of cellulose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Charophytes

A

(Supergroup Archaeplastida, Green algae) are closest relatives to terrestrial plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What evidence supports that charophytes are the closest relatives to plants?

A
  1. Rings of cellulose-synthesizing proteins (in other algae and plant organisms the cellulose forming proteins occur linearly)
    Many algae produce cellulose in cell walls,but charophytes and land plants have distinctive circular rings of proteins in the plasma membrane
  2. Flagellated sperm
    In plant species that have flagellated sperm, they most resemble the sperm in charophytes compared to other algae
  3. Formation of phragmoplast
    Microtubules and associated proteins present in charophytes and land plants after cytokinesis, guiding the assembly of cell plate formation

• Molecular analyses of nuclear, mitochondrial and chloroplast DNA also support this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the benefits of moving to land?

A

Moving to land is beneficial: (unlimited Co2 nutrients from soil more light)
• Sporopollenin is a polymer that prevents desiccation (Common in charophytic algae living at the edge of shallow ponds)
• More unfiltered sunlight, carbon dioxide, nutrients in soil -> life is good!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the challenges of moving to land?

A

Water is scare, harder to disperse sperm

• Have to grow against gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Sporopollenin

A

A durable polymer that covers exposed zygotes of charophyte algae and forms the walls of plant spores, preventing them from drying out
adaptation for life on land

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are some adaptations of plants to allow for survival on land?

A

Accessory pigments to help with UV protection, antioxidant effects

Cuticle -> waxy layer on the outer epidermis to help prevent desiccation

Stomata (pores) -> allow exchange of carbon dioxide and oxygen (photosynthesis is efficient even more because you have regulated gas exchange)
(Can close in periods of hot, dry conditions to prevent water loss )

Formed symbiotic relationships with fungi (roots did not immediately
happen) with mycerizae

Developed meristems to allow for vertical growth

Alternation of generations life cycle

Analysis of fossilized spores shows plants colonized land ~450 million years ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Stomata

A

A microscopic pore surrounded by guard cells in the epidermis of leaves and stems that allows gas exchange between the environment and the interior of the plant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cuticle

A

A waxy covering on the surface of stems and leaves that prevents desiccation in terrestrial plant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How can plants be classified?

A

Plants can be broadly classified based on the presence of vascular tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

vascular tissue

A

Plant tissue consisting of cells joined into tubes that transport water and nutrients throughout the plant body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What do non vascular plants include?

A

(bryophytes)
Liverworts
Mosses
Hornworts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What can vascular plants be divided into

A

comprises about 93% of all extant plant specie
Seedless vascular plants
Seedplants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What do Seedless vascular plants include?

A

Lycophyta (club mosses, spike mosses, quillworts

Monilophytes (ferns, horsetails, whisk ferns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What do Seedplants include?

A

Gymnosperms (ginkgos, cycads, gnetophytes, conifers)

Angiosperms (flowering plants)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Seedless vascular plants

A

An informal name for a plant that has vascular tissue but lacks seeds. Seedless vascular plants form a paraphyletic group that includes the phyla Lycophyta (club mosses and their relatives) and Pterophyta (ferns and their relatives).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which phylum has the most species?

A

Angiosperms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is an example of a grade?

A

A group, such as the bryophytes or seedless vascular plants, is sometimes referred to as a grade
monilophytes and lycophytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the monilophytes closely related to?

A

even though monilophytes and lycophytes are all seedless plants, monilophytes share a more recent common ancestor with seed plants
As a result, we would expect monilophytes and seed plants to share key traits not found in lycophyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

seed

A

An adaptation of some terrestrial plants consisting of an embryo packaged along with a store of food within a protective coat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

gymnosperms

A

A vascular plant that bears naked seeds—seeds not enclosed in protective chambers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

angiosperms

A

A flowering plant, which forms seeds inside a protective chamber called an ovary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

herbaceous

A

non woody liverworts (phylum Hepatophyta), mosses (phylum Bryophyta), and hornworts (phylum Anthocerophyta).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Describe the general life cycle of plants

A

1) Gametophyte produces haploid gametes (1n) via mitosis
2) Two gametes (1n) come together via fertilisation to produce a diploid zygote (2n)
3) The zygote (2n) develops into the multicellular sporophyte
4) The sporophyte (2n) produces unicellular haploid spores (1n) by meiosis
5) The spores (1n) develop into multicellular haploid gametophytes (1n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are liverworts and hornworts named for?

A

Liverworts and hornworts are named for their shapes, plus the suffix wort

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

ii

A

Phylogenetic analyze suggest bryophytes diverged early in plant lineage evolution

Earliest spores of plants (450-470 million years ago) more similar to liverwort spores (most basal group)

~430 million years ago spores similar to mosses and hornworts showed up in the fossil record

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What stage is dominant in bryophytes?

A

Bryophytes have a dominant haploid stage
gametophyte stage
they are usually larger and longer-living than the sporophytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

gametophyte

A 
In organisms (plants and some algae) that have alternation of generations, the multicellular haploid form that produces haploid gametes by mitosis. The haploid gametes unite and develop into sporophytes.
(gamete producing bodies)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Protonema

A

threadlike filaments that develop into “buds” which grow via a meristem to produce the gametophores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Gametophore

A

“gamete bearer”, produces gametes via mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Rhizoids

A

“root-like” filaments that anchor the gametophyte (not true roots)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Gametangia

A

produces the gametes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Archegonia

A

female, produces the egg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Antheridia

A

male, produces sperm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

sporophytes

A

(spore producing bodies)

Bryophytes have the smallest sporophytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Seta

A

stalk supporting the sporangium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Foot

A

absorbs nutrients from the gametophyte, supports the seta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Capsule

A

sporangium, produces spores via meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Peristome

A

“teeth” on the capsule to regulate spore dispersal (open when its wet enough let some spores and close when its too dry)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Describe the bryophyte life cycle

A

1) Spores (1n) develop into threadlike protonema
2) Protonema (n) produces “buds” the develop into gametophytes (n)
Gametangia
Antheridia -> male, sperm
Archegonia -> female, egg
3) Sperm must swim through water to reach the egg (Gametes produced via mitosis) (need access to water for fertilization)
4) Zygote develops into a sporophyte embryo (2n)
5) Sporophyte grows a seta that emerges from the archegonium
6) Attached by the foot, the sporophyte (2n) remains nutritionally dependent on the female gametophyte (n)
7) Meiosis occurs in the 2n capsule, producing spores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Describe bryophytes

A

Common in moist forests and wetlands, moist bare soil

Many associate with nitrogen-fixing bacteria

Can survive harsh environments (cold, dry)

Some Sphagnum moss species comprise peat

Many bryophyte species also have a medicinal or cultural importance in many Indigenous nations
(Bandages for wounds, baby diapers)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Why are bryophytes ecologically important?

A
  • Help retain moisture
  • Help retain nitrogen within the environment
  • Can tolerate complete water loss and can re-establish when moisture returns -> poikilohydric

Some Sphagnum moss species comprise peat
Preserves organisms from decaying due to the low temps, pH, and oxygen levels of peatlands
Important fuel source (Finland and Ireland uses a lot of it!)
Horticultural nutrient to help retain moisture in soils
Carbon sink -> 30% of the world’s carbon is stored in peatlands comprising 3% of Earth’s surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What were seedless vascular plants the first to do? When did they arise?

A

First to grow tall due to the rigid structure of vascular tissues

Arose ~425 million years ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Compared to nonvascular plants, Seedless vascular plants had:

A
  • Branched sporophytes now dominant stage
  • Not nutritionally dependent on the gametophyte

Still lack true roots

Vascular tissues
Xylem -> water transport, structural support
Phloem -> nutrient transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Xylem

A

water transport, structural support Vascular plant tissue consisting mainly of tubular dead cells that conduct most of the water and minerals upward from the roots to the rest of the plant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Phloem

A

nutrient transport
Vascular plant tissue consisting of living cells arranged into elongated tubes that transport sugar and other organic nutrients throughout the plant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Describe the fern life cycle

A

1) Sporangia release spores (n). Spores develop into a bisexual photosynthetic gametophyte antheridia and archegonia are produced on the same plant
2) Each gametophyte (n) produces antheridia and archegonia via mitosis. Sperm usually fertilizes the egg of another gametophyte
3) Sperm uses flagella to swim to the egg, attracted via positive chemotaxis to the archegonium
4) Zygote (2n) develops into a new sporophyte (2n), which grows out of the archegonium of the parent gametophyte
5) Sporophytes (2n) produce sori, clusters of sporangia (2n) which will produce spores via meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the xylem composed of?

A

Composed of tracheids and vessel elements, strengthened by lignin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is the phloem composed of?

A

Composed of sieve tube elements and companion cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

i

A

Allows plants to grow tall and still get nutrients to leaves
Allows plants to outcompete shorter plants for light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

tracheid

A

A long, tapered water-conducting cell found in the xylem of nearly all vascular plants. Functioning tracheids are no longer living.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

lignin

A

A hard material embedded in the cellulose matrix of vascular plant cell walls that provides structural support in terrestrial species.

58
Q

Describe the evolution of roots in Seedless vascular plants

A

Vascular tissues are also found in roots

Roots absorb water and nutrients from the soil, anchors the plant

59
Q

Describe the evolution of evolution of leaves Seedless vascular plants

A 
Leaves increase surface area for photosynthesis  
Megaphylls 
Microphylls 
Shoot system
Root system
60
Q

Megaphylls

A

larger, more evolutionarily advanced

A leaf with a highly branched vascular system, characteristic of the vast majority of vascular plants

61
Q

Microphylls

A

smaller, supported by a single strand of vascular tissue (Lycophytes)
In lycophytes, a small leaf with a single unbranched vein.

62
Q

Shoot system

A

is comprised of the above ground organs of the plant (leaves, stems)

63
Q

Root system

A

is comprised of the below ground organs

64
Q

Sporophylls

A

Modified leaves that bear sporangia

65
Q

sori

A

A cluster of sporangia on a fern sporophyll. Sori may be arranged in various patterns, such as parallel lines or dots, which are useful in fern identification

66
Q

strobili

A

The technical term for a cluster of sporophylls known commonly as a cone, found in most gymnosperms and some seedless vascular plants
found in lycophytes

67
Q

i

A

Fern sporophylls produce sori (sing. sorus)
Lycophytes (clubmosses and allies) produce strobili (sing. strobilus), which are little “cones”
Angiosperms (covered later) have modified sporophylls called carpels and stamens

68
Q

Most seedless vascular plants are..

A

homosporous

69
Q

homosporous

A

a plant species that has a single kind of spore(One type of sporangium that produces one kind of spore )
develops into a bisexual gametophyte
Ex. Ferns

70
Q

heterosporous

A

(mosses, all seed plants)
Referring to a plant species that has two kinds of spores: microspores, which develop into male gametophytes, and megaspores, which develop into female gametophytes

71
Q

Megasporophylls

A

(“female spore leaves”) which produce megasporangia

72
Q

megasporangia

A

female spore bearing structures

73
Q

Microsporophyll’s

A

“male spore leaves”) which produce microsporangia

74
Q

microsporangia

A

“male spore bearing structures”)

75
Q

Lycophyta

A

Clubmosses, spikemosses, quillworts
Most ancient group
Carboniferous period(359-299millionyears ago)
Used to be massive (2m wide!), but changing drier climate meant only the small ones were able to survive

76
Q

Monilophyta

A

Ferns, horsetails, whisk ferns
Devonian origins
Ferns are most diverse, ~12,000 species
More closely related to seed plants than lycophytes
• Have leaves, roots
~15 species of horsetails exist today (Equisetum spp.)
Whisk ferns (Psilotum sp.) are considered “living fossils”

77
Q

How are seedless vascular plants diverse?

A
  1. Modified leaves allow for reproduction
  2. Most seedless vascular plants are homosporous
  3. Some seedless vascular plants are heterosporous
78
Q

Spike Moss

A

Phylum: lycophyta

Habitat: marshy areas or as submerged aquatic plants

Sporophytes: upright stems

Leaves: many small leaves

Types of sporangia: heterosporous

79
Q

Quillwort

A

Phylum: lycophyta

Habitat: aquatic

Sporophytes: *

Leaves: single sporophyll

Types of sporangia: heterosporous*

80
Q

Club Moss

A

Phylum: lycophyta*

Habitat: *

Sporophytes: horizontal stems

Leaves: strobili

Types of sporangia: homosporous

81
Q

Fern

A

Phylum: monilophyta

Habitat: tropical to temperate

Sporophytes: megaphylls

Leaves: large leaves called fronds, often divided into leaflets*

Types of sporangia: most homosporous

82
Q

Horsetail

A

Phylum: monilophyta*

Habitat: marshy places & along streams*

Sporophytes: vegetative & reproductive stems

Leaves: rings of leaves

Types of sporangia: homosporous with cones releasing spores that typically give rise to bisexual gametophytes*

83
Q

Whisk Fern

A

Phylum: monilophyta*

Habitat: species of the genus Timesipteris, closely related to whisk ferns are found only in the South Pacific*

Sporophytes: dichotomously branching, lacks roots

Leaves: reduced

Types of sporangia: homosporous

84
Q

Describe the process of Homosporous spore production

A

sporangium on sporophyll -> single type of spore -> typically a bisexual gametophyte -> eggs OR sperm

85
Q

Describe the process of Heterosporous spore production (all seed plants) FOR EGGS

A

MEGAsporangium on MEGAsporophyll( -> MEGAspore -> female gametophyte -> eggs

86
Q

Describe the process of Heterosporous spore production (all seed plants) FOR SPERM

A

MICROsporangium on MICROsporophyll -> MICROspore -> male gamete -> sperm

87
Q

Describe the adaptations of Seed plants

A

Seeds
Reduced gametophytes (in bryophytes it was obvious in ferns the sporophyte was dominant but gametophyte was still visible)
Heterospory
Ovules and pollen

88
Q

Describe the Reduced gametophytes in seed plants

A

(in bryophytes the sporophyte is nutritionally dependent on the gametophyte, but in seed plants its other way around)
Microscopic
Tiny gametophytes can develop directly in the sporangium (sporophytes)
( Protection from the elements such as UV radiation, desiccation )
Gametophytes nutritionally dependent on the sporophyte now

89
Q

Most seed plants are…

A

heterosporous

90
Q

integument

A

2n Layer of sporophyte tissue that contributes to the structure of an ovule of a seed plant.
(sporophytic tissue that envelopes and protects the megasporangium)

91
Q

What is unique about seed plants?

A

Seed plants retain the megasporangium within the parent sporophyte

92
Q

How many integuments do gymnosperms or angiosperms have?

A

Gymnosperms -> 1 integument

Angiosperms -> 2 integuments

93
Q

Ovule

A

megasporangium (2n) + megaspore (n) + integuments (2n)

94
Q

where does the female gametophyte develop?

A

The female gametophyte will develop within the ovule from a megaspore and produces one or more eggs.

95
Q

pollen grain

A

(n) -> develops from a microspore and contains the male gametophyte enclosed within a pollen wall
Pollen grain ≠ male gametophyte
Inside = male gametophyte (n), outside pollen wall = secrete by microsporocytes (2n), contains sporopollenin

96
Q

Pollination

A

transfer of pollen to the ovule through a pollen tube in the micropyle of the ovule

97
Q

What can help ID a plant species?

A

Shape of pollen grains and outer wall spikes can ID

98
Q

What are advantages of pollen grains

A

can travel large distances without needing to swim in water

99
Q

If a sperm fertilizes an egg,…

A

zygote will grow into a sporophyte

100
Q

what develops into a seed

A

, the whole ovule develops into a seed: the embryo, with a food supply, packaged within a protective coat derived from the integument(s).

101
Q

What advantages do seeds provide over spores?

A

In non-vascular plants, spores could be released in a dormant state that germinates when conditions are good; their small size allows for this
However, spores are a single cell
No food supply

In seed plants, the ovule develops into a multicellular seed, which can remain dormant for longer periods of time
Embryo
Food supply
Protected seed coat (develops from the integument)

102
Q

seed plant history

A

Seed plants share characteristics that arose during the Devonian period (380 million years ago)
• Archaeopteris was heterosporous, though it did not make seeds

103
Q

When was the first evidence of seed plants recorded?

A

First evidence of seed plants themselves arose around 360 million years ago based on fossil record
55 million years before Gymnosperms
> 200 million years before Angiosperms

104
Q

Cycads

Cycadophyta

A

palm like leaves, large cones
~300species
Have flagellated sperm (suggests descent from seedless vascular plants
Most endangered -> 75% species threatened by habitat destruction

105
Q

Gnetophytes

A

Gnetum,Ephedra,Welwitchia
Tropical and desert habitats
Welwitschia mirabilis can live 1000s of years, deserts in SW Africa
Ephedra has ~40 spp., desert shrubs
Gnetum has ~35 spp., tropical trees, vines, shrubs in Africa and Asia

106
Q

Ginkgos

Ginkgophyta:

A

Ginkgobiloba,“maiden-hair”tree
Have flagellated sperm
Deciduous, fan-like leaves that turn gold in autumn
Tolerant to pollution
Only plant males because female seeds stink as they decay

107
Q

Pinophyta; Conifers

A

Pines, Spruce, Fir, junipers, larch, sequoia
The largest and most diverse gymnosperm phylum (~600)
Most species have woody cones (junipers have fleshy cones) and are evergreen
Some species are deciduous (larch, tamarack, some redwoods)
Leaves are needle-like (Pines, spruce) or scale-like (redwoods)
Huge economic importance (lumber, chemical compounds (taxol from Pacific yew))

108
Q

Describe the evolutionary history of gymnosperms

A

Earliest Gymnosperm fossils are ~305 million years old
Lived in moist Carboniferous ecosystems still dominated by lycophyte sand other seedless vascular plants
Survived better in drier climates due to seeds and pollen, thicker cuticles and small surface area of their needles (leaves)

109
Q

What are some things common to all gymnosperms?

A

Increasing dominance of the sporophyte

Seed as a resistant, dispersible stage in the life cycle

Pollen as an air born eagent brining sperm to the female gametophyte

All are heterosporous

Most produce cones: ovulate cones(female)and pollen cones(male)
• The scales on the cones are specialised sporophylls

Wind is the primary mode of dispersal

110
Q

Describe the pine life cycle

A

1) In most conifer species, each tree has both ovulate (female) and pollen (male) cones (often occur on the same plant but pollination wouldn’t occur on same plant they would go to different plant)
2) Microsporocytes divide by meiosis to produce microspores (n). The microspore develops into a pollen grain (the male gametophyte (n) + surrounding wall (2n))
3) An ovulate cone scale has 2 ovules, each containing a megasporangium. Only 1 ovule is shown here.
4) Pollination occurs when the pollen grain reaches the ovule, germinating to form a pollen tube that grows through the megasporangium
5) While the pollen tube develops, the megasporocyte (2n) undergoes meiosis. Producing 4 haploid cells. Only 1 survives as the megaspore (n)
6) The megaspore develops into a female gametophyte(contained withing megasporangium) that contains 2-3 archegonia, each of which will form an egg
7) By the time eggs are mature, sperm cells are fully developed and travel down the pollen tube for fertilization (the leftover gametophyte tissue becomes a food source)
8) Fertilization usually occurs 1 year after pollination. All the eggs may be fertilized, but only 1 zygote develops into an embryo (2n).

The ovule becomes a seed (embryo + food supply + seed coat)

111
Q

Angiosperms

A

“Flowering plants” (seeds are contained within food no longer naked)

112
Q

Dispersal vectors of angiosperms

A

Wind: common in grasses, temperate tree species
Animals: fruit-eating animals, hummingbirds
Insects: bees, moths, flies

113
Q

flower

A

In an angiosperm, a specialized shoot with up to four sets of modified leaves, bearing structures that function in sexual reproduction

114
Q

Sepals

A

outermost whorl of sporophylls; usually green (like on a bud)

115
Q

Petals

A

showy, inner whorl; attracts pollinators

116
Q

Stamens

A

microsporophyll’s that produce microspores that develop into pollen grains
• Composed of anthers and filaments

117
Q

Carpels

A

syn.Pistal)->megasporophylls that produce megaspores that develop into female gametophytes
• Composed of the stigma,style,and ovary

118
Q

What can flowers vary in?

A

Can vary in their symmetry
Can vary in their floral parts (some have decorative stamens, some have 4 petals etc. can help us distinguish the species)
Can be annual (1 year), biennial (every 2 years), or perennial (every year)

119
Q

fruits

A

ovary wall that has thickened around the seeds

120
Q

What do fruits do?

A

• Protects the seeds and aids in dispersal
Can be fleshy or dry
Have adaptations to allow for dispersal

121
Q

What adaptations do fruits have to allow for dispersal

A

Propellers(mapleseeds)
parachutes(Dandelions for wind dispersal)
rough coats to stick to animals (burrs on dogs)
Sweet tasting fruit(so animals eat and poop out the seeds in a new location

122
Q

Describe the angiosperm life cycle

A

1) In the megasporangium, the megasporocyte divides by meiosis, producing 4 megaspores of only which 1 survives
2) On the anther, each microsporangium contains microsporocytes that divide by meiosis, producing microspores
3) A microspore develops into a pollen grain. The generative cell of the male gametophyte will divide, forming 2 sperm. The tube cell will produce the pollen tube
4) After pollination, eventually two sperm cells are discharged in each ovule
5) Double fertilisation occurs. One sperm fertilizes the egg, forming the zygote. The other sperm fertilizes the central cell, forming a 3n endosperm (food supply)
6) Zygote develops into an embryo that is packaged into the seed with the food supply (fruit not shown)
7) The seed germinates and grows into a new sporophyte (2n)

123
Q

Describe the male gametophyte structure of angiosperms

A

Prothallial cells -> produce the generative and tube cells
Generative cell -> produces sperm
Tube cell->produces the pollen tube
Exine -> outer wall composed of sporopollenin

124
Q

Prothallial cells

A

produce the generative and tube cells

125
Q

Generative cell

A

produces sperm

126
Q

Tube cell

A

produces the pollen tube

127
Q

Exine

A

outer wall composed of sporopollenin

128
Q

Describe the female gametophyte structure of angiosperms

A

Also called the embryo sac
Antipodal cells -> cells at the far end of the gametophyte
Polar nuclei (inside the central cell) -> forms the endosperm following double fertilization
Synergids -> near the egg, aid in fertilization (help direct pollen tube to the egg)
Egg -> female gamete

129
Q

Antipodal cells

A

cells at the far end of the gametophyte

130
Q

Polar nuclei

A

inside the central cell) -> forms the endosperm following double fertilization

131
Q

Synergids

A

near the egg, aid in fertilization (help direct pollen tube to the egg)

132
Q

Egg

A

female gamete

133
Q

endosperm

A

In angiosperms, a nutrient-rich tissue formed by the union of a sperm with two polar nuclei during double fertilization. The endosperm provides nourishment to the developing embryo in angiosperm seeds.

134
Q

cotyledons

A

a seed leaf of an angiosperm embryo

135
Q

Basal Angiosperms

A

~100)
Water lilies, Star anise and relations, Ambrorella
Oldest Angiosperm linegage
Spiral arrangement of floral parts

136
Q

Magnoliids

A

(~8000 species)
Magnolias,Laurels,BlackPepperplants(Pipernigrum,plant of the day)
Woody and herbaceous species
Spiral arrangement of floral parts

137
Q

Monocots

A

(~70,000 species)
• Orchids, grasses ,palms
• Fibrous rootsystem
• Simple leaves with parallel veins

138
Q

Eudicots

A

~170,000 species)
Legumes, roses, flowering trees (oak, walnut, etc)
Taproot system
Leaf venation is netted

139
Q

Describe Angiosperm Evolution

A

Widespread appearance in the fossil record (~140 million years ago)
• Originated in the Cretaceous period
• Archaefructus is a fossil angiosperm, with a herbaceous and bulbous growth habit

140
Q

i

A

One current hypothesis of the phylogeny of Angiosperms is based on morphological and molecular evidence
• Living Angiosperms are monophyletic
• Evolution often was a result of plant-animal interactions
Anti-herbivory compounds, mutualistic co-evolution of animal pollinators
Flower shape and colour can be very specific to pollinator preference

141
Q

What are some characteristics of monocots?

A

embryos- one cotyledon

leaf venation:veins usually parallel

stems: vascular tissue scattered
roots: root systems usually fibrous (no main root)
pollen: pollen grain with one opening
flowers: floral organs usually in multiples of 3

142
Q

What are some characteristics of eudicots?

A

embryos- 2 cotyledon

leaf venation: veins usually netlike

stems: vascular tissue usually arranged in a ring
roots: taproot usually present
pollen: pollen grain with 3 openings
flowers: floral organs usually in multiples of 4 or 5

BIOLOGY 1030 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions