diversity in living organisms [animalia alone

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Diversity in living organisms

PLANTAEDONE BY, DINESH KUMAR

Bryophyte is a traditional name used to refer to all embryophytes (land plants) that do not have true vascular tissue and are therefore called "non-vascular plants".[1] Some bryophytes do have specialized tissues for the transport of water; however, since these do not contain lignin, they are not considered to be true vascular tissue.As of 2014, it is uncertain whether bryophytes are a natural ormonophyletic group or a paraphyletic group, but the name is convenient and remains in use as a collective term for mosses, hornworts, and liverworts. Bryophytes produce enclosed reproductive structures (gametangia and sporangia), but they produce neither flowers norseeds, reproducing via spores. The term "bryophyte" comes from Greek βρύον, bryon, "tree-moss, oyster-green" + φυτόν – phyton"plant".

Pteridophytes or Pteridophyta, in the broad interpretation of the term , are vascular plants (plants with xylem and phloem) that reproduce and disperse via spores. Because they produce neither flowers nor seeds, they are referred to as cryptogams. The group includes ferns, horsetails, clubmosses, spikemosses and quillworts. These do not form a monophyletic group, because ferns and horsetails are more closely related to seed plants than to lycophytes (clubmosses, spikemosses and quillworts). Therefore, pteridophytes are no longer considered to form a valid taxon, but the term is still used as an informal way to refer to ferns (monilophytes) andlycophytes, and some recent authors have used the term to refer strictly to the monilophytes

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