A L C O S O B J E C T I V E 1

Diversity of Plants
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Anthocerophyta – Hornworts
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Bryophyta – Mosses
Hepatophyta – Liverworts
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Lycophyta – Clubmosses and Spikemosses
Pterophyta – Ferns and Horsetails
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Cycadophyta – Cycads
Ginkgophyta – Ginkgo and Maidenhair
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Gnetophyta
Coniferophyta – conifers
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Anthophyta – Flowering plants

Diversity of Plants
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Bryophytes
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Nonvascular seedless plants
Small, grow near water
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Dominant gametophyte
Originated 475 mya
Division Anthocerophyta
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Hornworts
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Sporophyte typically 5cm in height
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~ 100 extant species

Phaeoceros laevis
Diversity of Plants
Anthoceros agrestis

Diversity of Plants
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Division Bryophyta
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Mosses
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Sporophyte typically
~15cm in height
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Form dense mats
15 000 extant species
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Found on every continent except Antarctica

Diversity of Plants
Pyrrhobryum spiniforme Sphagnum sp.

Diversity of Plants
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Division Hepatophyta
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Liverworts
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Sporophyte less than 5cm in height
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Typically found in tropical or subtropical regions
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~9000 extant species

Diversity of Plants
Frullania ericoides Marchantia polymorpha

Diversity of Plants
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Seedless vascular plants
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Evolution of vascular tissue
Dominant sporophyte
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Originated 420 mya
Division Lycophyta
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Clubmosses and
Spikemosses
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~1200 extant species
Most primitive vascular plants

Diversity of Plants
Lycopodium tristachyum Selaginella apoda

Diversity of Plants
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Division Pterophyta
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Ferns, Horsetails and
Wisk ferns
12 000 extant species
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Thrive in temperate climates
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Dominated forest of carboniferous period

Diversity of Plants
Osmunda cinnamomea Polystichum acrostichoides

Diversity of Plants
Cheilanthes alabamensis Trichomanes petersii

Psilotum nudum
Diversity of Plants
Equisetum hyemale

Diversity of Plants
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Vascular seed plants
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Evolution of seeds
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Dominant sporophyte
Originated 360 mya
Division Cycadophyta
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Cycads
~100 extant species
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Grow exclusively in tropical habitats
Only species found wild in
U.S grows in Florida

Cycas circinalis
Diversity of Plants
Encephalartos sclavoi

Diversity of Plants
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Division Ginkgophyta
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1 extant species
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Ginkgo biloba
Cultivated trees
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Maidenhair tree
Fan-like leaves turn gold in autumn

Diversity of Plants
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Division Gnetophyta
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Gnetophytes
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75 extant species
Most species found in desert regions
Some species may live to be over 1000 years old

Diversity of Plants
Ephedra torreyana Welwitschia Mirabilis

Diversity of Plants
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Division Coniferophyta
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Conifers
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600 extant species
Most are evergreen
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Adaptations for conserving water

Pinus palustris
Diversity of Plants
Pinus taeda

Diversity of Plants
Taxodium distichum Juniperus virginiana

Diversity of Plants
 Division Anthophyta
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Flowering plants
Subdivided into
Monocotyledons and
Dicotyledons
Monocotyledons
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65 000 extant species
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Grasses, orchids, lilies and palms
Dicotyledons
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185 000 extant species
Shrubs, trees, cacti, wildflowers, garden flowers, vegetables and herbs

Digitaria sp.
Diversity of Plants
Andropogon glomeratus

Diversity of Plants
Hymenocallis coronaria Platanthera ciliaris

Myrica cerifera
Diversity of Plants
Smilax laurifolia

Acer rubrum
Diversity of Plants
Liquidambar styraciflua

Quercus rubra
Diversity of Plants
Quercus alba

Diversity of Plants
Spigelia marilandica Mitchella repens

Clitora mariana
Diversity of Plants
Trillium sp.

Dichotomous Keys
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Made up of set of numbered statements
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Each set deals with a single characteristic of the organism
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Leaf shape or leaf arrangement
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Bark and twig structure
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Flower arrangement and structure
A key to the trees of Alabama
 http://www.aces.edu/pubs/docs/A/ANR-0509/ANR-0509.pdf