Seedless Vascular Plants

• Tracheophytes have vascular tissue, which allowed them to grow larger than non vascular plants since they can transport water, nutrients, and waste
• Roots in tracheophytes allowed them to reach deeper water sources and provide structural support
• Dominant sporophyte generation, and lessening size of the gametophyte generation
• Roots, stems, and leaves developed through convergent evolution
• Club mosses (lycophytes)
  • Not true mosses
  • In the Carboniferous period they were as large as trees
  • Small narrow leaves with a central vein (lycophylls)
  • Sporangia are at the base of specialized sporophytes
  • Small, free living gametophyte organism
  • Motile sperm that need water as a transport medium
• Pterophyta:
  • Ferns:
  • Can be divided based on how spores develop
    • Eusporangiate: sporangium develops from many cells to produces many spores​
    • Leptosporangiate: sporangium develops from​

        a single cell and produces a small number​ of spores * Most abundant type of tracheophytes * Some surviving species are as large as trees * Have roots, stems, and complex leaves called euphylls * Fronds grow from the rhizome * Sporangia are called sori and are found on the underside of the frond * Small, free living, photosynthetic gametophyte * Motile sperm that needs water for transport

      of spores​

• Horsetails:
  • Historically were tree sized
  • Jointed stems and reduced scale-like leaves
  • Stems contain silica
  • Stems can be vegetive or reproductive
  • Photosynthesis only occurs in the stem
  • Most are homosporous
  • Small free living gametophytes
  • Motile sperm that needs water
• Whisk ferns:
  • Rootless, leafless sporophytes
  • Sporangia on tips of the stems
  • Tiny colourless gametophyte that is often symbiotic with fungi
  • Vascular tissue is produced in some gametophytes