Vascular Seed and Non-Seed Plants

Diversity of Seedless Vascular Plants

• Club mosses, also called spike mosses, and

ferns compose the seedless vascular plant group.

• Some seedless vascular plants have a strobilus in their sporophyte – a cluster of spore-bearing
structures.

Seedless Vascular Plants
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Diversity of Seedless Vascular Plants

Division Lycophyta

• Descendent from the oldest group of vascular plants

• Sporophyte generation of lycophytes is dominant

• Have roots, stems, and small, scaly, leaflike structures

• Many species are epiphytes – plants that live anchored to an object or another plant.

Seedless Vascular Plants
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Diversity of Seedless Vascular Plants

Division Pterophyta

• Includes ferns and horsetails

• Most abundant plants during the Carboniferous period (300-359 mya)

• Sporophyte produces roots and thick underground stem called a rhizome, a food-storage organ.

Seedless Vascular Plants
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Diversity of Seedless Vascular Plants

Division Pterophyta

• The familiar leafy fern fronds are the sporophyte generation

• Fern spores form in a structure called a sporangium.

• Clusters of sporangia form a sorus.

• Sori usually are located on the undersides of fronds.

Seedless Vascular Plants
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