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TRANSCRIPT
PLANT KINGDOM
By:
Dr.Ghasoun M.ali Wadai
What Is a Plant?
Multicellular eukaryotes that are
photosynthetic autotrophs
Cell walls made of cellulose
Store surplus carbohydrates as starch
Mostly terrestrial
Reproduction
Plants produce their gametes within
GAMETANGIA
Zygote develops into an embryo within a
jacket of protective cells
Embryophytes – a key adaptation to the
success of plants on land
ALTERNATION OF GENERATIONS
Occurs in life cycle of all plants
One generation is a multicellular haploid
condition and the next is a multicellular
diploid condition
Obstacles Plants Overcome
Absorb Minerals
Conserve Water
– Cuticle
– Stomata
– Guard Cells
Reproduce on Land
A Vascular System Enables
Plants to Thrive on Land
Most plants need a “plumbing” system
to transport water, minerals and
nutrients.
This system is known as
the VASCULAR SYSTEM.
Five Characteristics Unique to Land
Plants
Apical meristem – localized regions of active cell division in roots and shoots
Embryophtes – multicellular dependent embryos
Alternation of Generations
Walled spores produced in sporangia
Multicellular reproductive structures –antheridia and archegonia
Plant Classification
Non-flowering
Plants
Flowering
Spore-
bearingNaked
seeds
No
roots
with
roots
Mosses Ferns
Gymnosperms
1 seed-
leaf
2 seed-
leaves
Monocots Dicots
Plant Kingdom
Flowering
Plants
Non-flowering
Plants
. 3 groups
FernsMosses Gymnosperms
Non - flowering Plants
Do NOT produce flowers
A plant can be divided into 3 parts
Examples of Mosses
spores
Spore-producing capsule
.No true roots, No vascular tissues (no transport)
Characteristics of Mosses
.Simple stems & leaves
.Have rhizoids for anchorage
.Spores from capsules
(wind-dispersal)
.Damp terrestrial land
.Simplest plants
underground
stem
root
A leaf (finely
divided into
small parts)
.roots, feathery leaves & underground stems
Characteristics of Ferns
.have vascular tissues (transport & support)
.Damp & shady places
.Spore-producing organ on the underside of
leaves (reproduction)
needle-shaped leaves
Male cones
(in clusters)Female cones
(scattered)
.roots, woody stems
Characteristics of Gymnosperms
.needle-shaped leaves
.tall evergreen trees
.cones with reproductive
structures
.dry places
.vascular tissues (transport)
.naked seeds in female cones
. 2 groups
Monocotyledons Dicotyledons
Flowering
Plants
. roots, stems, leaves
. vascular tissues (transport)
. flowers, fruits (contain seeds)
Monocotyledons
Parallel veins
. one seed-leaf
Characteristics of Monocotyledons
. leaves have parallel veins
. herbaceous plants
. e.g. grass, maize
Dicotyledons
Veins in network
. two seed-leaves
Characteristics of Dicotyledons
. leaves have veins in network
. e.g. trees, sunflower, rose