HORSETAIL,CLUBMOSSES,AND FERNS are primitive land plants, which ,like higher plants , have stems,roots,and leaves,and vascular system that transport water, mineral and food .
However , unlike higher plants ,they do not produce seeds .when reproducing .There life-cycle involves two stages . In stage one , the saprophyte (green plant) produces spores in sporangla. In stage two , the spores germinate , developing into a small short lived gametophyte plants that produce male and female gametes , the gametes fuse to form a zygote. from which a new sporophyte plant develops .
Horsetail (phylum - sphenophyta )have erect green stems with branches arranged in whorls ; some stem are fertile and have a single spore producing strobilus (group of sporangia) at the tip.Clubmosses (phylum Lycopodophyta) typically have small leaves arranged spirally around the stem , with spores producing strobili at the tip of some stems .
Ferns (phylum Filicinophyta) typically have large pinnate fronds(leaves);sporangia , grouped together in sori , develop on the underside of fertile fronds.
However , unlike higher plants ,they do not produce seeds .when reproducing .There life-cycle involves two stages . In stage one , the saprophyte (green plant) produces spores in sporangla. In stage two , the spores germinate , developing into a small short lived gametophyte plants that produce male and female gametes , the gametes fuse to form a zygote. from which a new sporophyte plant develops .
Horsetail (phylum - sphenophyta )have erect green stems with branches arranged in whorls ; some stem are fertile and have a single spore producing strobilus (group of sporangia) at the tip.Clubmosses (phylum Lycopodophyta) typically have small leaves arranged spirally around the stem , with spores producing strobili at the tip of some stems .
Ferns (phylum Filicinophyta) typically have large pinnate fronds(leaves);sporangia , grouped together in sori , develop on the underside of fertile fronds.
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