What are Bryophytes ?

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Bryophytes are non-vascular embryophytes and the simplest group of land plants. They are called amphibians of plant kingdom, as they still require external water for fertilization. The main plant body is a haploid gametophyte called gametophores, which may be thalloid as in lower bryophytes like Riccia and Marchantia or a leafy, branched axis as in mosses like Funaria.

Root like rhizoids arise at the base economic are unbranched, and unicellular in thalloid forms, but branched and multicellular with oblique walls in mosses. True roots, leaves and stems are absent in bryophytes. The male sex organ is called as antheridium and female as archegonium. Biflagellate sperms of bryophytes need water for their movement to reach archegonium. The diploid sporophyte or sporogonium developes from zygote and is partially or completely dependent on gametophyte. It is differentiated into foot, seta and capsule and bears haploid spores formed by meiosis. The spores germinate into gametophyte.

Funaria gametophores are about 1-3 cm in height with root-like rhizoid, shoot like axis or cauloid and leaf like phylloid. Moss plant reproduces mainly by sexual method and rarely by vegetative methods. Vegetative reproduction occurs by secondary protonema and vegetative propagules like bulbil and gemma.

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Funaria is monoecious, bearing male and female branches. Club-shaped antheridia intermingled with sterile paraphyses are borne at the tip of male branch and flask-shaped archegonia with a stalk, a venter and a long neck are intermingled with paraphyses and appear in clusters at the tip of female branch. One not fertilization, the zygote develops into a sporophyte differentiated into foot, seta and capsule.

Capsule is a pear-shaped with a basal sterile apophysis, central fertile theca and upper cap-like operculum. Theca possesses a central sterile region called columella, surrounded by spore sacs that bear numerous haploid into a branched filamentous protonema (juvenile stage). Lateral buds develop on it grows into deafy gametophores (adult stage). Peat deposits of Sphagnum (peat moss) are used as fuel, for dressing wounds, packing plants and flowers. Mosses are also great soil builders.

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