Please enable JavaScript.
Coggle requires JavaScript to display documents.
Vascular Plants Without Seeds (The Megaphyll Line of Evolution:…
Vascular Plants Without Seeds
Early Vascular Plants
Rhyniophytes
Prostate rhizome, and terminal sporangia
Naked stems, equal dichotomous branching
Xylem Structure of Early Vascular Plants
Endarch protostele and exarch protostele
Zosterophyllophytes
Lateral sporangia
Enations increased photosynthetic surface area
Small herbs without secondary growth
The Microphyll Line of Evolution: Lycophytes
Heterospory
Extinct and extant sporangia are in compact groups for protection
Some species became heterosporous, microspores and megaspores
Extant Genera
Lycopodium species are homosporous, spores germinate and grow into bisexual gametophytes
Selaginella is heterosporous
Ligule helps distinguish between the two.
Morphology
Lycophytes evolved from zosterophyllophytes
Differences: large enations, single trace of vascular tissue
True roots anchor firmly
The Megaphyll Line of Evolution: Euphyllophytes
Monilophytes
Euphyllophytes are united by 3 synapomorphies
Their roots have exarch xylem, they have megaphylls, and they have a 30-kilobase inversion
Equisetophytes
Classified as division Arthrophyta/Sphenophyta
Horsetails/scouring rushes
Umbrella shaped spoangiophore
Monopodial growth
Origin of Megaphylls (Euphylls)
Three distinct types of Homoplasic structure
Enations/Microphylls of zosterophyllophytes and lycophytes
Leaves on gameotophytes of nonvascular plants
Megaphylls
Ferns
First appeared in Devonian Period
Leptosporangiate ferns
Fern sporophyte consists of a single axis
Eusporangia and Leptosporangia
Trimerophytes
Overtopping and pseudomonopodial branching
3 Genera of extinct plants: Trimerophyton, Psilophyton, and Pertica
The Term "Vascular Cryptogams"
Production is hidden due to the lack of seeds
Lack seeds, flowers, fruits, etc.
"Ferns and fern allies"
