Kingdom Plantae
• Plants are members of the kingdom Plantae
whose cells are eukaryotic (have a nucleus),
have a cell wall made of cellulose, and
contains chloroplasts with pigments such as
chlorophyll a and b that help the plant to carry
out photosynthesis.
KEY CONCEPT
Plant life began in the water and became adapted to
land.
Early Plants
• They were very similar to algae that we are
familiar with. They were dependent on water
for reproduction, and only with the evolution
of the seed were plants able to survive on dry
land.
Plant Kingdom
Non-flowering
Plants
Flowering Plants
(Angiosperms)
Non - flowering Plants
Bryophytes
Seedless
Vascular
Spore-producing Plants
Gymnosperms
Seed-producing
Non - flowering Plants
Bryophytes
Seedless
Vascular
Plants
Gymnosperms
Do NOT produce flowers
Mosses and their relatives are seedless
nonvascular plants.
• Nonvascular plants grow close
to the ground to absorb water
and nutrients.
• Seedless plants rely on freestanding water for
reproduction.
• Liverworts belong to phylum
Hepatophyta.
– often grow on wet rocks or in
greenhouses
– can be thallose or leafy
Bryophytes
• Appearance
– Mosses: grow in clumps (green mass)
• Anchor
– No true roots,
– they have rhizoids
• Transport
– No vascular tissue so no transport
Bryophytes
• Habitat
– Damp terrestrial environments
• Reproduction
– Spores form capsules that are dispersed
by the wind
– Requires water
• Examples
– Mosses, liverworts, hornworts
20.2 Classification of Plants
TEKS 5B, 7D, 8B, 8C
• Mosses belong to phylum Bryophyta.
– most common seedless nonvascular plants
– sphagnum moss commonly used by humans as “peat”
Bryophyta:
Mosses
Moss
Spore-producing capsule
spores
Liverworts and Hornworts
Liverwort
Hornwort
Seedless Vascular Plants
• Appearance
– Feathery leaves, underground stems
• Anchor
– Roots, underground stems
• Transport
– Vascular tissue (also provides support)
20.2 Classification of Plants
TEKS 5B, 7D, 8B, 8C
Club mosses and ferns are seedless vascular plants.
• A vascular system allows club mosses and ferns to grow
higher off the ground.
• Both need free-standing water for reproduction.
• Club mosses belong to phylum Lycophyta.
– not true mosses
– oldest living group
of vascular plants
20.1 Origins of Plant Life
TEKS 7A, 7E, 8C, 12A
• A vascular system allows resources to move to different
parts of the plant.
–
–
–
–
collection of specialized tissues
brings water and mineral nutrients up from roots
disperses sugars from the leaves
allows plants to grow higher off the ground
water
and
mineral
nutrients
sugars
21.1 Plant Cells and Tissues
TEKS 5B, 10B, 10C
• Vascular tissue transports water, minerals and organic
compounds.
– two networks of hollow
tubes
– xylem transports water
and minerals
– phloem transports
photosynthetic products
stem
leaf
root
21.2 The Vascular System
TEKS 4B, 5B, 10B, 10C
Water and dissolved minerals move through xylem.
• Xylem contains specialized cells.
– vessel elements are short and wide
– tracheid cells are long and narrow
– xylem cells die at maturity
tracheid
vessel
element
21.2 The Vascular System
TEKS 4B, 5B, 10B, 10C
Phloem carries sugars from photosynthesis throughout
the plant.
• Phloem contains specialized cells.
– sieve tube elements have
holes at ends
– companion cells help sieve
tube elements
– unlike xylem, phloem tissue is
alive
21.2 The Vascular System
• Water travels from roots to the top of trees.
– absorption occurs at roots
– cohesion and adhesion in xylem
– transpiration at leaves
TEKS 4B, 5B, 10B, 10C
21.2 The Vascular System
TEKS 4B, 5B, 10B, 10C
• The cohesion-tension theory explains water movement.
– Plants passively transport water through the xylem.
– Cohesion is the tendency of water molecules to bond
with each other.
– Adhesion is the
tendency of water
molecules to bond
with other
substances.
Seedless Vascular Plants
• Habitat
– Damp, shady environments
• Reproduction
– Spores are produced on underside of leaves by the
sorus
– Requires water
• Examples
– Ferns, horsetails, club mosses
Fern
Young fern leaf (circinate)
Sorus: fern spore-producing
organ
Horsetail
Club moss
Tips of branches
called strobili have
spore bearing parts
on them.
Seed plants include cone-bearing
plants and flowering plants.
• Seed plants have several advantages over their
seedless ancestors.
– can reproduce without free-standing water, via
pollination
– pollination
occurs when
pollen meets
female plant
parts
– seeds
nourish and
protect plant
embryo
– seeds allow plants to disperse to new places
20.2 Classification of Plants
TEKS 5B, 7D, 8B, 8C
• Gymnosperms do not have seeds enclosed in fruit.
– most gymnosperms are cone-bearing and evergreen.
– the cone is reproductive structure of most
gymnosperms.
– pollen is produced
in male cones.
– eggs are produced
in female cones.
– seeds develop on
scales of female
cones.
Ginko
Cycad
Cycadophyta
Male cone
Female cone
Conifer
Needle-shaped leaves
Male cones
(in clusters)
Female cones
(scattered)
20.2 Classification of Plants
TEKS 5B, 7D, 8B, 8C
• Angiosperms have seeds enclosed in some type of fruit.
– A flower is the reproductive structure of angiosperms.
– A fruit is a mature ovary of a flower.
• Angiosperms, or flowering plants, belong in phylum
Anthophyta.
20.3 Diversity of Flowering Plants
TEKS 7B, 7D, 8B
Flowering plants have unique adaptations that allow them
to dominate in today’s world.
• Flowers allow for efficient pollination.
– animals feed on pollen or nectar
– pollen is spread from plant to plant in process