Bryophytes Biology Bryophytes Include Mosses and their relatives

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.

Sporophyte and Gametophyte

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