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