Bryophytes213-page1 - There are three Bryophyte Phyla:...

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Bryophytes - 1 There are about 20,000 species of Bryophytes, the plants that lack vascular tissue. They are found throughout the world, although more prevalent in moist and shady areas. Common Bryophyte Habit Bryophytes, especially mosses, are abundant in alpine and artic regions, where they are subjected to freezing. Others are adapted to deserts where they are desiccated most of the time. The moss, Sphagnum , is found in bogs world wide, and forms peat, a source of fuel when compacted, and a soil texturizer when less "decomposed". Lignite, a low-grade coal, contains peat. About 1% of the world’s land mass is comprised of peat bogs. (The United States is about 2% of the world’s land mass.) Associations of Bryophytes with mycorrhizae and with endosymbiotic cyanobacteria that fix nitrogen are common.
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Unformatted text preview: There are three Bryophyte Phyla: Bryophyta (Mosses) Hepatophyta (Liverworts) Anthocerophyta (Hornworts) The three phyla are distinguished from each other on variations in sporophyte structure and gametophyte morphology. The gametophyte generation is the predominant and assimilative stage in all bryophytes. Major Characteristics of Bryophytes Bryophytes lack vascular tissues so Bryophytes must absorb all water and nutrients at the surface and pass them from cell to cell. This dependence on cell-to-cell diffusion for transport places size restriction on bryophytes. Some mosses have modified water transport cells, call hydroids, that form a central hadrom conducting tissue and a few have solute conducting cells, called leptoids that form a leptom....
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This note was uploaded on 01/08/2012 for the course BIO 213 taught by Professor Makina during the Fall '09 term at SUNY Stony Brook.

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