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(Chapter 21. Vascular Plants w/ seeds) - Coggle Diagram
Chapter 21. Vascular Plants w/ seeds
Early Vascular Plants
Rhyniophytes
characteristics
equal dichotomous branching
epidermis with a cuticle
simple bundle of xylem
cortex of parenchyma
central cells were sporogenous
fossils
example
Zosterophytes
small herbs without secondary growth
plants grew as small bunches
named after genus
Zosterophyllum
three distinct features
lateral sporangia
sporangia opened transversely along top edge
xylem was an exarch protostele
Vascular Cryptograms
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They lack:
flowers
seeds
reproduction is hidden
"Crypto"
fruits
refers to ferns
fern allies
The Megaphyll Line of Evolution: Euphyllophytes
origin of megaphylls (euphylls)
leaves evolved from branch systems
distinct homoplasic structure
present in all seed plants, ferns, and equisetophytes
telome theory
megaphyll evolution
Equisetophytes
consist of several genera of extinct plants
monopodial growth
specialized reproductive structures
aerial stems
whorl of fused leaves at the nodes
jointed structure
division of Arthrophyta
Ferns
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leaves can be leathery or delicate
most are homosporous
sporophyte consist of a single axis
can be found in almost any habitat
underside of leaf is known as the sori
each node has a leaf trace
Trimerophytes
controlled positioning of branches
advancement out of ryniophytes
have unequal branching
Monilophytes
examples
fern allies
Psilotales
ferns
Marattiales
two sister clades
The Microphyll Line of Evolution: Lycophytes
extant genera
have prostrate rhizomes
small herbs
approximately 200
true roots
short upright branches
morphology
earliest lycophytes were similar to zosterophyllophytes
important differences
contain a single developed trace of vascular tissue
large enations
evolution of true roots
optimized lycophyte sporophytes
heterospory
necessary precondition for evolution of seeds
cones/strobili
protect the species
compact groups
