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Vascular Plants
1. Internal conducting tissue (xylem & phloem)
2. True leaves
3. Roots for absorption, as well as anchorage
4. Gametophyte reduced, sporophyte dominant
5. Primitive vascular has no seeds, spores instead
Major Divisions• Psilotophyta – whisk ferns
• Lycophyta – club moss, quillworts, ground pines, spike pines,
• Sphenophyta – horsetails
• Pterophyta – ferns
Psilotophyta• Whisk ferns – Simplest vascular plant, no
leaves or roots. Fossil records from 400 mya
– Structure• Forking stem, arise from rhizomes• Enations – tiny green leaf-like tissue without
veins, spirally arranged• Photosynthetic stem, core of xylem & phloem
Psilotophyta• Reproduction –
– Sporangia releases spore, sporophyte generation visible
– Gametophyte generation minute, not visible
Psilotophyta
• Habitat – – Tropical & subtropical, southeastern U.S.
Lycophyta (Club mosses, Quillworts, Ground Pine, Spike Pines)
• True stems & leaves• Microphylls = small leaves• Structure
– Ground pine resembles little Christmas trees
– Leaves are whorled– Stems arise from rhizomes, as
well as adventitious roots– Cone-like reproductive structure
Lycophyta• Reproduction
– Sporophyll – sporangium bearing leaves produce spores by meiosis
– Strobili – cone like structure contains spores from meiosis
Lycophyta
• History & uses– Flashbulb powder– Powder can stop bleeding– Ornamental – floral design, Christmas decorations
• Habitat– Tropics and Coastal NW & NE North America
Sphenophytaa.k.a….
Snake Grass!!!
Sphenophyta (Horsetails, Scouring rushes)
• Silica deposits in epidermal cells of stem, used for scouring pots & pans
• Structure– 4-15 feet tall– Whorled branches– Tiny scale-like leaves – microphylls whorled
at nodes or joints– Photosynthetic stem with stomata and hollow,
central core
Sphenophyta
• Reproduction – – Fragmentation – asexual– Strobili produce spores with elaters (prevent
spores from sticking together and aid in spores dispersal)
– Gametophyte reduced, sporophyte visible
Sphenophyta
• History & uses– Food for humans & animals – can be dried &
ground into flour– Medicine – diuretic, antacid, TB, parasites,
gonorrhea– Silica – scouring, polishing, sharpening
Pterophyta“The ferns”
• Structure – – Sizes from 1 cm floating species to tropical 85
ft ferns
Pterophyta“The ferns”
• Structure continued…– Fern leaves – “megaphyll” –
dissected, multiple veins, very feathery
• Immature fronds called “fiddleheads”
Pterophyta“The ferns”
• Structure continued…– Stems arise from horizontal rhizomes– Adventitious roots also arise from rhizomes
Pterophyta“The ferns”
• Reproduction– Sorus – cluster of sporangia on underside of
frond; sporophyte phase
Pterophyta“The ferns”
• Reproduction continued…– Prothalus (Irish valentine) – green heart
shaped gametophyte– Small, 5-6 mm can be seen without
microscope, but generally no bigger than .25 inches
– One cell thick with rhizoids underneath surface
– Antheridium & archegonium produced on upper surface
– Spores develop from archegonium after fertilization, becomes the “fiddlehead”
Pterophyta“The ferns”
• History & uses – – House plants, outdoor ornamentals– Fern bark used in growing rare orchids– In tropics, used for clothing, shelter, baskets– Rhizome used as a vegetable– Medicine – coughs, colds, parasites,
toothaches, bleeding
Alternation of Generations
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