Economic Importance and Habitat of Bryophyta

• Ecological importance: They usually grow densely and so acts as soil binders. Liverworts and mosses growing on rocks and organic matter to the substratum after their death. It makes the surface suitable for the growth of higher plants. Thus they form an important community in plant succession.
• Medicinal uses: Decoction of Polytrichum commune is used to remove kidney and gall bladder stones. Decoction prepared by boiling Sphagnum in water for treatment of eye …

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Introduction to Pteridophyta

Kingdom – Plantae

All the multicellular eukaryotic plants are placed in Kingdom-Plantae. They are autotrophic i.e.. they manufacture their food by photosynthesis.

Following plant groups are included in Kingdom-Plantae

(1) ALGAE

(2) BRYOPHYTA

(3) PTERIDOPHYTA

(4) GYMNOSPERM

(5) ANGIOSPERM

• Term Pteridophyta was proposed by Haeckel
• The study of Pteridophytes is known as pteridology.
• Pteridophytes are known as reptiles of plant kingdom (because like reptiles are the …

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General Characters of Pteridophytes

• Pteridophytes are also called as vascular cryptogams. Pteridophytes are vascular plants i.e.. xylem and phloem are present in it. In Pteridophytes, vessels in xylem and Companion cells in phloem are absent.
• But exceptionally xylem of Pteridium, Selaginella and Marsilea contains false vessels.
• Note:- Secondary growth is absent (due to absence of cambium) in Pteridophyta but exceptionally secondary growth is present in stem of Isoetes.
• Pteridophytes are called as…

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Life Cycle of Pteridophytes

• Plant is sporophyte, i.e.. diploid.
• Most of the Pteridophytes are homosporous i.e.. only one type of spores is formed during reproduction.
• Examples are Lycopodium, Pteridium, Equisetum and Dryopteris
• Exception - Some Pteridophytes are heterosporous i.e.. two types of spores microspores and megaspores.
• Examples are Selaginella, Isoetes, Marsilea, Salvinia, Azolla, Stylites, Pilularia and Regnellidium
• Formation of spores takes place in sporangia. Sporangia are form…

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