Download Kingdom Plantae The Diversity of Plants - Biology102-104

Moss exhibiting gametophyte and sporophyte stages.
Fig. 23-5b, p. 372
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Evolved supporting structures
Conserve water (vessels that transport water
and nutrients to all parts of the plant)
Dispersal of gametes and zygotes independent
of water
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Roots or root like structures
Waxy cuticle
Stomata
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The most widespread group of plants have:
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Especially well-protected and well-provisioned embryos
Waterless dispersal of sex cells
Pollen, seeds
In flowering plants: flowers and fruits
Sori on fern
Seeds in
Papaya
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Bryophytes (nonvascular plants)
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Require moist environment to reproduce
Straddle aquatic and terrestrial life
Vascular plants
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Able to move to drier habitats
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Lack true roots, leaves, and stems
Have rhizoids which are root-like anchoring
structures that bring water and nutrients to plant
body
Lack well-developed structures for conducting
water and nutrients
Gametophyte stage most prominent
Require water for reproduction
Size is limited
Acquire water by either slow diffusion or poorly
developed conducting tissues to distribute water and
nutrients
 Lack stiffening agent
 Most are less than 1 inch
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Liverworts
Hornworts
Moss
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Have vessels (specialized conducting cells)
Vessels contain lignin (stiffening substance)
Above structures allow this group to grow
taller
Diploid sporophyte is larger than in
bryophytes
In bryophytes the haploid gametophyte is
more evident
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Seedless plants
Seed plants
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Like bryophytes, have swimming sperm and
require water for reproduction
Propagate by spores
3 groups
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Club mosses
Horsetails
Whisk ferns
Ferns
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Small – few inches
tall
Leaves are small
and scale like
Genus Lycopodium –
ground pine
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Most less than 3 feet
tall
Genus Equisetum
Leaves are tiny
scales on branches
Called “scouring
rushes”
Deposit large
amounts of silica in
their outer layer of
cells – produce
abrasive texture
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Most diverse of group
In tropics, grow very tall
Haploid spores produced in sporangia which
form on special leaves of the sporophyte
Spores dispersed by wind
Give rise to tiny haploid gametophyte plants,
which produce sperm and eggs
As in bryophytes, gametophytes lack
conducting vessels and the sperm must swim
through water