Biology

Bryophyta

There are about 23,000 species of Bryophyta in the world, of which Mosses constitute a major portion of this group. Mosses grow abundantly in Bangladesh. Characteristics of Bryum moss are described here. Bryum grows on damp soil, on the tree trunk and on the old walls etc. Characteristics:

  1. The plant body is divided into Rhizoid (instead of root), Leaf and Stem.
  2. There is no vascular tissue in its body.
  3. Male and female plants are different.
  4. Bi-flagellate sperms, grown in male plants, united with the non-motile egg. grown in the female plant, initiate the sporophyte.
  5. Sporophytes are developed on the top of the female plants.
  6. Spores produced in the capsules germinate to produce algae like filamentous Protonema.
  7. Moss plants develop from the Protonema.

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fig: Moss Bryum  

Importance of Moss plants: Mosses help to grow soil on the stone surface. It helps to hold water. Pit coal is developed from Sphagnum (a Moss).