Kingdom: Plantae
Characteristics of Plants
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Eukaryotic
Multicellular
Carry out photosynthesis
Cells have a cell wall made of cellulose
Mostly land dwelling
Develop from embryos that are protected by
tissues of parent plant
Life cycles
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Plants go through alternation of generations
One generation is haploid called gametophyte
One generation is diploid called sporophyte
Haploid spores produce plants which
eventually produce gametes which fuse to
produce diploid zygote that grows into a
sporophyte plant
• These generations can look quite different
from one another
Five Major Groups of Plants
Green Algae
• Green algae has recently been reclassified as
belonging to the Kindom Plantae
• Green algae has cell walls and photosynthetic
pigments that are identical to plants
• Other algae remain in the Kingdom Protista
Five Major Groups of Plants
Seedless Non-Vascular Plants
Mosses and Relatives
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These plants are known as Bryophytes
Grow close to the ground in damp locations
Do not have seeds or stems
Do not have any rigid support structures such
as lignin-reinforced cell walls
• Do not have any vascular tissue to transport
water through the plant
Seedless Non-Vascular Plants
Mosses and Relatives
• Bryophytes comprise nearly 10% of all plant
species
• The gametophyte generation is the dominant
generation
• Male and female gametes are produced in
separate reproductive structures
• Sperm are flagellated and must swim through
water to the eggs
Five Major Groups of Plants
Seedless Vascular Plants:
Ferns and Relatives
• Contain conducting tissues called xylem and
phloem which transport materials throughout
the plant
• This development allowed the ferns to
become tall and successful on dry land
• The dominant generation is sporophyte
Reproduction in Ferns
• Ferns produce gametes in structures on the
underside of the gametophyte
• Ferns need water to complete their life cycle
because sperm have to swim through a film of
water to fertilize the eggs
• The brown “dots” on the underside of the
mature (sporophyte) fronds are spore
capsules containing many haploid spores that
will produce gametophytes
Five Major Groups of Plants
Seed-producing Vascular plants
Gymnosperms
• Conifers such as pine, fir, spruce, redwood and
cedar trees – cone bearing plants
• Plants that bear “naked” seeds – seeds not
enclosed in an ovary (fruit)
• Seeds are plant embryos covered in a
protective coat along with food
• The gametophyte is smaller than in ferns and
mosses
Gymnosperm
Reproduction in Gymnosperms
Five Major Groups of Plants
Flowering Plants
Angiosperms
• The reproductive structures are the flowers
• Angiosperm means “enclosed seed”
• The gametophytes develop within the flowers
of angiosperms
• Flowers have many adaptations that attract
organisms to help transfer pollen
• Once pollination occurs, the ovary develops
into a fruit
Angiosperm fruit
Life cycle of
an
Angiosperm
Parts of a Flower
Stigma
Stamen
(male)
Anther
Filament
Style
Ovary
petals
ovule
sepal
Carpel/
Pistil
(female)
Five Major Groups of Plants