Characteristics of tracheophytes
- Vascular tissue
- Sporophyte dominant (persistant, free living, and photosynthetic)
- Sporangium w/ tapetum layer
Tapetum
Nutritive layer found below sporangium wall
- Breaks down as spore develops
- Releases nutrients
Early Vascular Plants
Extinct
- Simple dichotomously branching stems
- Leafless
- Terminal sporangia
2 Groups of Tracheophytes
- Lycophytes
- Euphilophytes (ferns and seed plants)
Lycophyta
Sp Div-5th Eco Div-tropical Old and many turned into coal 1. Microphylls: derived leaves 2. Dichopodial Roots
Microphyll
Small leaves w/ single vein
Origin: enation w/out vascular tissue
-Lycophyta
Dichopodial Roots
Dichotomously branch
-Lycophyta
Euphyllophyte Characteristics
Ferns and seed plants
- Leaves called megaphylls
- Monopodial roots
- Multiflagellate Sperm
Megaphylls
Leaves, large and richly veined
Origin: lateral branches that flattened out and developed mesophyl webbing
Pteridophyta (Ferns)
Sp Div-3rd
Eco Div- understory forest plants and epiphytes
Eusporangia Ferns
Very old
- Psilotales and Equisetales
- All have eusporangium
Eusporangia
Normal sporangia w/ wall, tapetum, spores
-No special features
Psilotum (Eusporangiate)
3 lobed eusporangia
- Dichotomous branching
- No roots or leaves
- Growth form looks like vascular plants
Equisetales (Eusporangiate)
Ancient group-many extinct tree-size lineages but now only small herbaceous plants
- No leaves
- Unique stems, strobili, and spores
Equisetum Stems
Jointed, hollow, and rigid
- Green and photosynthetis
- Silicon in epidermis
- Series of canals make hollow pith
Equisetum Spores
Green and photosynthetic
4 coiled elaters that twist and untwist in response to humidity
Leptosporangiate Ferns Characteristics
Order: Filicales
- Leptosporangia
- Fronds
- Fiddleheads
- Rhizomes
- No secondary growth
- Many epiphytes
Leptosporangium
Sporangium w/ stalk, lip cells, and annulus w/ thick walls
-Catapults spores away
Fronds
Fern leaves
- Usually compound
- Leaflet called pinnae
- Attached to rachis
Circinate Vernation
Coiling of young fern leaves
-Called a fiddle head
Protects leaf tip as it develops
Fern Stems
Usually rhizomes
- Underground and produce leaves and adventitious roots
- No secondary growth
Sorus
Discrete groups of sporangia
-Occur on underside of frond
Indusium
-Cover sori
Protect sporangium from drying out
Fern Gametophytes
Heart shaped body called prothallus
- Green and photosynthetic
- Rhizoids to anchor
