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Bryophytes. Biology. Bryophytes. Include Mosses and their relatives. They are highly dependent on water. Lack of vascular tissue. Because they lack vascular tissue, bryophytes are small. They need to get water by osmosis and can only be a few centimeters above ground for this to occur.
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Bryophytes Biology
Bryophytes • Include Mosses and their relatives. • They are highly dependent on water.
Lack of vascular tissue • Because they lack vascular tissue, bryophytes are small. • They need to get water by osmosis and can only be a few centimeters above ground for this to occur.
Standing water • Bryophtes must live in places where there is standing water for at least part of the year. • They produce gametes that must swim through water to reach other individuals.
Three groups of plants that bryophytes include - • Mosses, Liverworts and Hornworts.
Where do mosses grow? • In areas with water, such as in swamps and bogs, near streams and in rain forests.
Polar Regions • Mosses can tolerate low temperatures, so they are the most abundant plants in polar regions.
Do mosses have stems? • Though you will see thin, upright shoots on moss plants, they aren’t considered to be true stems, as they lack vascular tissue.
Mature Gametophyte of Liverworts • When liverwort gametophytes mature, they produce structures that look like tiny green umbrellas.
Gemmae • Small multicellular reproductive structures of liverworts. • When haploid cells are washed out of a gemma cup, the gemmae can divide by mitosis and produce a new individual.
Soil • Liverworts and hornworts are generally found only in soil that is damp nearly year round.
Photosynthesis • The Gametophyte generation carries out most of the plant’s photosynthesis.
Fertilization • Gametophyes must be soaked with rainwater or dew, so that the sperm cells can swim to the egg cells.
Protonema • When moss spores germinate, they grow into a tangled mass of green filaments called a protonema.
Bryophyte Reproductive structures • Antheridia – Male – Sperm • Archegonia – Female – Egg cells