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KINGDOM PLANTAE
Challenges to moving to land
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How to obtain water
How to prevent water loss
Reproduction
Getting needed nutrients
Non vascular
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Algae
Mosses
Hornworts
Vascular Plants
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Fern
Gymnosperms
Angiosperms
GENERAL CHARACTERISTICS
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Ancestors of today’s land plants were green algea
Hundreds of thousands of species in all environments
Eukaryotic, multi-cellular organisms
Cuticle cover plant that prevents water loss
Stomata – openings in plant that facilitate gas exchange
Photosynthesis – gas exchange, 02 and C02 that
produce energy in the form of sugar C6H1206 + 02
General Characteristics
Male gametophyte – Antheridia produce sperm
Female gametophyte – Archegonia produce egg
Zygote produce by egg and sperm fusion
All Plants Have Alternation Of Generations
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Gametophyte (N) Haploid - Sporophyte (2N) Diploid
Non vascular plants
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Three phyla, collectively called bryophytes
Small
Need water for reproduction
No true roots, stems or leaves
Seedless
No vascular tissue
Mosses
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Phylum Bryophyta – Mosses 16,000 species
Rootlike Rhizoids – absorb nutrients, water
Antherdia and archegonia both present on many
mosses
Typical alternation of generation life cycle
Haploid generation dominant
Peat moss (sphagnum) Dead cells hold water –
used in poor soil conditions
Liverworts
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Phylum Hepatophyta – liverworts, 6,000 species
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Thallus (thalli resemble liver) – flattened lobe
structure of plant
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Gametophyte dominant
generation
Hornworts
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Phylum Anthocerophyta – Hornwarts, 100
species
Sporophyte is “needlelike”, grows out of
gametophyte – gives rise to the name hornwort
Sporangium release spores – grow to
gametophytes
Seedless Vascular Plants
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Have vascular tissue, xylem and phloem that provide
support and conduction
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Xylem – conducts water from roots to stems and leaves
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Phloem – transports food in
any direction
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Have true stems, leaves and
roots
Club Mosses
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Phylum Lycophyta – Club Mosses, 1200 species
Evergreens – sometimes used in christmas
decorations
Ferns
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Phylum Pteridophyta – ferns, 11,000 species
Found in swamps, marshes, woodlands, fields,
some arctic and aquatic species
Alternation of generation life cycle –
sporophyte is dominate generation
Parts of Ferns
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Rhizomes - horizontal underground stem
Fronds – compound leaves form from rhizomes
Fiddlehead – tightly coiled young frond
Sorus – cluster of sporangia on the underside of
frond that produce spores
Antheridia and Archegonium are produced by
Fern Parts
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Fiddlehead
Frond
Sorus
Wisk Ferns
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Phylum Psilophyta – Wisk ferns, 12 species
Mainly in tropics
No true roots, rhizomes
Sporangia at tip of stems produce spores
Horsetails
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Phylum Pteridophyta
Horsetails – grow in wet, moist areas
Seed Plants
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Two types of seed plants are:
Gymnosperm – “naked seed” seed usually not
enclosed in ovary - examples are:
Ginko tree
Pine tree
Cycads
Seed Plants cont.
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Angiosperms “covered seed” Seed enclosed in
ovary, flowering plants – examples are:
oak
magnolia
corn
grass
Seed Plants
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Seed plants are superior to spore plants in three
ways, they are:
1. The seeds are protected by a seed coat
2. Seeds contain young plant with roots, leaves,
and stem
3. Seed contains food supply so after
germination embryo is nourished
Gymnosperms
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Gymnosperms consist of pines, fir, spruce,
hemlock
Sequoia
Redwood
Bristlecone
77 foot girth
tallest 364 oldest 5000 yrs
Gymnosperms – seed plants
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Phylum Coniferophyta (conifers) – pines, firs,
spruce, cedar, redwood
Redwoods and giant sequoia and the earths
tallest trees
Most are evergreen, few shed leaves
Seeds are stored in female cones, and sperm in
the male cones
Conifers
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Importance – food, shelter, wood, paper, drugs,
landscaping, turpentine – 630 species
Male
life cycle
female
Cycads
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Phylum Cycadophyta – cycads – 100 species
Most species extinct – separate sexes
Tropical and subtropical
Stout trunk like stems, leaves resemble palms
Popular ornamentals, many endangered
Ginkgo
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Phylum Ginkgophyta – one living species
Separate sexes, female tree seed gives off rancid
odor
Leaves bright yellow, deciduous (leaves fall off)
Ginko biloba – taken to improve memory
Gnetophytes
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Phylum Gnetophyta – vines, shrubs, and trees
Grow in desert and tropical climates
Jointed stems, some resemble horsetails
Ephedra used to treat high blood pressure and
was used for dieting
Angiosperms
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Angiosperms – “covered seed” flowering plants
Phylum Anthophyta – 300,000species
Most successful of all plants
Small to large – violets and eucalytus tree
Reproduce sexually –flowers - form seeds within fruits
Xylem tissue has vessel elements for conducting water
Phloem tissue has sieve tube elements for conducting
sugar
Economic value
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All major food crops are angiosperms
Rice, wheat, barley, corn
Valuable lumber – oak, walnut, etc
Cotton and linen
Wheat
Rice
Corn
Phylum Anthophyta
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Class Monocotyledons – monocots – 90,000
species
One cotyledon - embryonic seed leaf
Parallel venation
Scattered vascular bundles
Flower parts in multiples of 3
Endosperm – nutritive tissue in seed
Herbaceous
Palms, grasses, orchids, irises, onions and palms
Monocotyledons - Monocots
Dicotyledones - Dicots
Differences in Monocots and Dicots
Feature
Flower parts
Leaf venation
Vascular bundle
Roots
Secondary growth
Seeds
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Monocot
3’s
parallel
scattered
fibrous
absent
one cotyledon
Dicot
4’s
netted
in a circle
taproot
present
two
cotyledons
Differences in Monocots and Dicots
Flower Parts
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Sepals, petals, stamens, and Pistil
1. complete flowers have all 4 parts
2. incomplete flowers are missing at least one
3. flowers are the reproductive shoots
4. perfect flowers have both stamens and
pistil
5. imperfect flowers have stamen or pistil, but
not both
Flower Diagram
Plant Kingdom Structure and
Growth
Almost all plants have roots, stems, and leaves
 Plants range in size and shape
 Non woody plants (herbaceous) do not produce
lignin
- Herbaceous plants – no lignin
- Annuals - live one year, corn, garden plants
- Biennials – two year cycles, cabbage, queen
anne’s lace
- Annuals and biennials die at end of season
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Structure and Growth
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Annuals – non woody – one year growth
Structure and Growth
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Biennials – two year cycle die after 2 years
Structure and Growth
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Woody plants – trees and shrubs – parts persist
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Perennials – are woody plants and “few” herbaceous
plants that live more than two years
All woody plants are perennials
Some live for 100’s, 1000’s of years
Woody perennials that shed leaves are “deciduous”
Woody perennials that keep their leaves in cold
weather are “evergreens”
Structure and Growth
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Perennials – woody plants live 2 or more years
Structure and Growth
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Plant body consist of the root and shoot system
Roots – underground system that absorb water
and nutrients
Shoots – stems and leaves absorb carbon dioxide
Both used in their environment for plants
benefit
Both made up of different tissue types
Structure and Growth
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Three tissue systems of vascular plants are:
system
function
1. ground tissue - photosynthesis, storage
support
2. vascular tissue - conduction and support
3. dermal tissue - protection, covers plant
Tissue Systems/Function of Vascular Plants
System
Ground
Tissue
Parenchyma
Cells
Function
Parenchyma storage, starch, oil, water
photosynthesis, soft part
of plant, secrete resins,
hormones
Collenchyma Collenchyma support – cell alive at
maturity, “strings” in
celery, beans
Sclerenchyma Sclerenchyma support, usually dead at
maturity
nuts, fruits, veins of leaf
System
dermal
Tissue
Tissue
epidermis
outermost
layer of
herbaceous
plants
Cells
epidermal cells
guard cells
Function
protection,
prevent water loss
regulate
stomata
System
Tissue
Dermal
periderm
(suberin)
outer bark
of stem & root
Cells
Function
cork
waterproof
dead at
maturity
protection
cork
cambien
meristematic cells
form new cells
cork
parenchyma
storage
Plant Growth - Meristems
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Two types of plant growth are:
primary – increase in stem and root length all woody and non weedy
exhibit
apical meristem - increase in length in tips of roots, shoots, and
buds
root tips – protective layer that protect roots
secondary – increase in girth of plant – mostly in gymnosperms &
woody dicots – tissues that grow are wood and bark
lateral meristem – growth along the entire length of stems
and root
Plant Growth
Lateral meristem secondary growth along the entire
length of the stem and root
vascular cambien – long thin layer of
meristematic cells that form thin cylinder in
stems and roots – adds more cells to secondary
xylem (wood) and to secondary
phloem (inner bark)
cork cambien – divides and forms cork cells and
outer bark, cork and cork parenchyma for storage
bark – outermost covering of stems and roots –
inner bark is secondary phloem and outer bark is
periderm
Apical and Lateral Meristems
Leaf Structure and Function
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Leaves are the main structure for photosynthesis
and water conservation
Leaf shapes are characteristic of different
species
Nodes – where leaves connect to the stem
Leaf
Leaf
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Transpiration – water loss in plants, light, heat,
wind, and humidity affect
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Stomata – openings on leaf that allow gas
exchange
- blue light wavelength opens stomata
- low levels of carbon dioxide open stomata
- circadian rhythm – 24 hour biological clock opens
stomata
Leaf
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Modified leaves – spines on cacti
tendrils of peas and squash modified leaves
bulbs of onions and tulips are modified leaves
carnivorous plants – pitcher have modified leaves
Leaf Arrangement
Leaf parts
- cuticle – waxy layer of epidermis, prevents water
loss
- pallisade mesophyll – where photosynthesis occurs
- vein – where xylem and phloem located
- spongy mesophyll – where diffusion of gases occurs
- stomata - opening surrounded by guard cells
where gas exchange takes place
Parts of Leaf
Stems and Transport
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Provide support, stronger than roots
Provide support for leaves and flowers
Provide transport of sugar, water and minerals
Produce buds that make new stems, leaves and
flowers
Vascular system throughout stems, leaves, and
roots
Stems amd Transport
woody dicot
non-woody monocot
Stem
Woody plants and secondary growth
- only woody dicots and cone bearing evergreens
have secondary growth
- secondary growth causes an increase in girth of
stems and roots
- vascular cambien gives rise to secondary growth
- primary xylem and phloem are replaced during
growth by secondary xylem and phloem - wood
Stem
- sapwood is the term for younger wood- lighter –
wood of conifers
- heartwood is older wood in center of tree that isn’t
functional - wood of flowering plants
- cork cambium produces periderm – bark, cells of
periderm contain suberin that make them
impenetrable to water, insects, fungus, etc
- annual rings determine age
Stem Structure
Roots
Roots
Anchor, absorb, conduct water and minerals and
food storage
 Two types of roots are:
- taproot – one main root formed from seedling –
found in dicots and gymnosperms
- fibrous – many roots of similar size – monocots
Root cap – protective thimble-like cap – covers
root tip
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Roots
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Root hairs – increase absorption
Epidermis covers root
Cortex – parenchyma cells, no collenchyma or
sclerenchyma cells
Endodermis – inner layer regulate water and
nutrients
Pith – center of many roots and stems
Root Types
Prop roots – advantageous roots that develop
from branches – grow downward and provide
support
Root types
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Buttress root – concentrated and surface root
that absorb minerals from rotting leaves – found
mainly in tropics
Root types
Pneumatophores – “breathing roots” – grow from
submerged part of root in swampy of tidal
environment allowing gas exchange
Root Types
Epiphytes – aerial roots that anchor plants to bark
or branch
hydroponics