Tracheophytes: The Vascular Plants
xylem (for transporting water and mineral nutrients)
phloem (for transporting sugars from leaves to the rest of the plant)
larger and more complex sporophyte is more prominent demonstrate increased levels of
organization
Major evolutionary advances of the vascular plants
Major evolutionary advances of the vascular plants
Major evolutionary advances of the vascular plants
Division Lycophyta: club mosses oldest extant group of vascular
plants sporangia organized into strobili
(sing.: strobilus) may be either HOMOSPOROUS or
HETEROSPOROUS Leaves that contained vascular
tissue
REPRESENTATIVE SPECIES
Lycopodium isospores bisexual gametophyte
REPRESENTATIVE SPECIES
Selaginella small spores (microspores) that
germinate to produce the male gametophyte
larger spores (megaspores) that germinate to produce the female gametophyte
Division Sphenophyta: scouring rushes
leaves produced at a node (WHORLS)
production of isospores spores bearing elaters (devices to
aid in spore dispersal) gametophyte is small,
photosynthetic and free-living Silica concentrated jointed stems
Division Psilophyta
traditionally considered to be the oldest living lineage of vascular plants
lack roots stem is photosynthetic no leaves but rather minute enations
sporangia occur in fused groups (synangia)bilobed synangia of Tmesipteristrilobed synangia of Psilotum
resembles what paleobotanists believe Cooksonia
CHARACTERISTICS:
1. Underground rhizome2. Unicellular rhizoids3. Erect stems dichotomize into the
main photosynthetic organ
REPRESENTATIVE species
Psilotum (2 species) and Tmesipteris (2-5 species)
Division Pteridophyta
reproduce by spores from which the free-living bisexual gametophyte generation develops
megaphyllous leaves leaf is called a frond
fiddleheads central axis of a compound frond is
called the rachis
ANTHERIDIUM
ARCHAEGONIUM
READING ASSIGNMENT
READ ON GYMNOSPERMS AND ANGIOSPERMS You may also use Biology by Campbell
and Reece