LAB 9 Flashcards
Seedless vascular plants dominated the landscape from ______ to _______
Mid-Silurian
Carboniferous
Two groups studied in lab
Lycopodiphyta
Polypodiophyta
What do Lycopodiophyta and polypodiophyta posses
-Well developed leaves
-sporophylls
-roots
-true vascular tissue
Xylem and phloem
How do seedless vascular plants reproduce
windblown spores
Oldest extant vascular plant division
Lycopodiophyta
Lycopodiophyta contain
Club mosses and spike mosses
What are distinguishing characteristics of lycopodiophyta
- microphylls with only a single unbranched vein
- transverse dehiscence of sporangia
- stroboli
Club mosses develop around roots along a horizontal stem called a
rhizome
Homosporous
-producing a single type of spore that bears both male and female organs
Club mosses are _______
homosporous
Where do strobili occur
at the end of an upright stem
Characteristics of lycopodium (club moss) spore
- high fat content
- large surface area per area unit volume
- flammable
Microphylls of spike mosses
- simple a scale like
- branching vascular trace
Microphyll of club moss
- thickly cover stem
- may or may not branch
What type of spores do spike mosses produce
- Heterosporous
- Megaspores
Heterosporous
produce two types of spores
Ancestors of horsetails reached their peak in the
late paleozoic
Synapomorphy for horsetails
helical thinking of the sporangial wall
Horsetails may be the
oldest surviving genus
Characteristics of horsetails
- jointed stem
- rough texture
- leaves are whorled
Extant gymnosperm phyla
Cycadophyta
Ginkgophyta
Gnetophta
Coniferophyta
Annulus
Ring or band of thickened cells that runs around the spherical sporangium
Blade
The leafy part of the frond
Costa
the mid vein of the pinna
