progymnosperm การใช้

• Noeggerathiales have been previously linked to horsetails and ferns, but are currently believed to be progymnosperms.
• These were joined by progymnosperms, which rooted up to about a metre deep, during the ensuing Frasnian stage.
• Rothwell's analysis separates the " trimerophytes " and progymnosperms, with only the latter being closely related to seed plants.
• In Late Devonian times, another group of progymnosperms gave rise to the first really large trees known as " Archaeopteris ".
• They probably evolved from a group of Late Devonian progymnosperms known as the Aneurophytales, which had large, compound frond-like leaves.
• These early seed plants ranged from trees to small, rambling shrubs; like most early progymnosperms, they were woody plants with fern-like foliage.
• It is grouped with " Pertica ", traditionally classified as a " trimerophyte " rather than a progymnosperm like " Tetraxylopteris ".
• The oldest fossil evidence of seed plants is of Late Devonian age, and they appear to have evolved out of an earlier group known as the progymnosperms.
• As taller and more complex plants evolved, modifications in the alternation of generations evolved; in the Paleozoic era progymnosperms reproduced by using spores dispersed on the wind.
• This occurred independently in several separate lineages of vascular plants, in progymnosperms like " Archaeopteris ", in Sphenopsida, ferns and later in the gymnosperms and angiosperms.
• The "'progymnosperms "'are an extinct group of woody, spore-bearing plants that is presumed to have evolved from the trimerophytes, and eventually gave rise to the gymnosperms.
• Rothwell's analysis separates " trimerophytes ", like " Pertica ", from progymnosperms, like " Tetraxylopteris ", with only the latter being closely related to seed plants.