Seedless Vascular Plants Part II

1. Flagellated sperm

2. Not monophyletic

3. Sporophytes are the larger generation

Three traits of seedless vascular plants

Flagellated sperm

•usually restricted to moist environments

Not monophyletic

•grouped based on shared key biological features

•referred to as a grade

Sporophytes are the larger generation

•The gametophytes are tiny plants that grow on or below the soil surface

Sporophylls

modified leaves with sporangia

sori

clusters of sporangia on the undersides of sporophylls

Strobili

cone-like structures formed from groups of sporophylls

homosporous

spore production of most seedless vascular plants

Heterosporous

spore production of all seed plants

1. Lycophytes

2. Monilophytes

Seedless vascular plants clades

1. club mosses

2. spike mosses

3. quillworts

Lycophytes 3 examples

1. fern

2. horsetails

3. whisk ferns

Monilophytes 3 example

small herbaceous plants

Surviving species of Lycophyta

1. vascular tissues

2. not true mosses

Club mosses and spike mosses have __________ and are _______

Ferns

the most widespread seedless vascular plants, >12,000 species

Horsetails

diverse during the Carboniferous period, but are now restricted to the genus Equisetum

whisk ferns

resemble ancestral vascular plants but are closely related to modern ferns

1. removed CO2 from atmosphere

2. global cooling

3. coal

SIGNIFICANCE OF SEEDLESS VASCULAR PLANTS (3)