Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 23: Seed Plants I: Seed Plants without Flowers - Coggle Diagram
Chapter 23: Seed Plants I: Seed Plants without Flowers
Concepts
alternation of heteromorphic generation
sporophyte temporarily dependent
evolution of seeds = evolution of vascular cambium
lignophytes: woody plants
spermatophytes: seed plants
2 major characters
manoxylic wood
pycnoxylic
Spermatophic (division)
Gymnospermae (class)
"naked ovules"
flat sporophylls
Angiospermae (class)
flowering
tubelike
Division Progymnospermophyta: Progymnosperms
Trimerophytes
evolved from rhyniophytes
pseudomonopodial branching
horsetails and ferns
Progymnosperms
3rd evolved
extinct
evolution of vascular cambium
Aneurophytes
relictual pro gymnosperms
shrubs to large trees
protosele primary xylem
webbing, not yet leaves
Archaeopteridales
trees, 8.4 m tall
siphonostele
planted branch system
spiral arranged simple leaves
heterosporous reproduction
Evolution of Seeds
fossil material
megasporangium
integument
micropyle
pollen chamber
Division Pteridospermophyta: Seed Ferns
seed ferns
Upper Devonian Period
grade rather than clade
woody plant w/ fern foliage that bore seeds
Pteridosperm
evolution from Aneurophytales
parenchyma, not trachieds
vascular cambium
Division Coniferophyta: Conifers
conifers
diverse
never vines, herbs, or annuals
no bulbs or rhizomes
simple needles or scales
lack sieve tubes
transfusion tissue
lack vessels
pines
monopodial
composed of trachieds
rays
resin canals
shoots
long shoots: tiny, papery leaves
short shoots: long needle leaves, axils
cones
pollen cones
simple
single short unbranched axis
microsporophylls
seed cones
compound
more complex
axillary buds
cone bracts
ovuliferous scale
Division Cycadophyta: Cycads
stout trunks
compound leaves
less than 1 or 2 m
no ovules
bark and leaf bases
dioecious
seed and pollen cones on separate plants
Division Cycadeoidophyta: Cycadeoids
all extinct
stomatal complexes
leaf trace organization
cones contain
microsporophylls
megasporophylls
Division Ginkgophyta: Maidenhair Tree
single living species
stout trunk
look like large dicot
many branches
broad leaves
no exact ancestor
Division Gnetophyta
3 groups of enigmatic plants
Gnetum
30 species
vines or small shrubs
Ephedra
40 species
tough shrubs and bushes
Welwitschia mirabilis
only species
leaves reduced and scalelike
gymnosperms with vessels
vessel element evolves from tracheid
