BRYOPHYTA

• BRYOPHYTA (Greek word meaning moss plant)
• BRYOPHYTA

  • First plants to evolve (1. liverworts, 2. hornworts, 3. mosses)
  • Mostly small and lack vascular tissues
  • Lack true leaves, seeds, and flowers
  • Have hair-like rhizoids instead of roots
  • Niches in moist habitats but are not very efficient in absorbing water
  • Depends on moisture to reproduce and disperse
  • Reproduction is characterized by alteration of generations type of life cycle
• HEPATOPHYTA (Liverworts)

  • Spore-producing non-vascular, thalloid or leafy plants with a life cycle like that of mosses
  • Small, generally inconspicuous plants that grow on moist soil, rocks, old stumps, and tree bark
  • Common in coniferous forests
  • Lack stomata (although some may have surface pores thought to be analogous to stomata)
  • Flattened, lobed structure
  • Have thallus (hair-like rhizoids that anchor the plant to the soil) on its underside
• HEPATOPHYTA (Liverworts)

  • Doctrine of signatures: forms of liverworts was suggested to be the lobes of animal liver hence the thalloid liverworts were thought to have medicinal value for the treatment of liver ailments
  • Leafy Liverworts

   Have branching

   Leafy rather than lobed thallus

   Superficially resembles to mosses

   Have prostrate, leafy ‘shoots’ and rhizoids

   ‘leaves’ consists of a single undifferentiated cell

   Some reproduce asexually by forming small balls of tissue called gemmae (sing gemma)
• ANTHOCEROPHYTA (Hornworts)

  • Spore-producing, non-vascular thalloid plants with a life cycle similar to that of mosses
  • Small group of about 100 species of bryophytes whose gametophytes superficially resemble those of the thalloid of liverworts
  • Live in disturbed habitats such as fallow fields and roadsides
• ANTHOCEROPHYTA (Hornworts)

  • Has single large chloroplast in each cell which resembles algae than that of plant cells
  • Archegonia (female) and antheridia (male) are embedded in the thallus; after fertilization, the needle-like sporocyte projects out of the gametophyte of the thallus forming a spike, or ‘horn’ (thus the name hornwort)
  • Single gametophyte often produces multiple sporocytes
  • Meiosis occurs, during which spores from within each sporangium which then splits open form top to release the spores; each spore has the potential to rice to a new gametophyte thallus
• ANTHOCEROPHYTA (Hornworts)

  • Sporocytes of hornworts, unlike those of mosses and liverworts, continue to grow from their bases for the remainder of the gametophyte’s life
• BRYOPHYTA - (Mosses)

  • Mosses usually lives in dense colonies or Bedson moist soil, rocks, or tree bark
  • Has tiny hair-like structures called rhizoids and an upright stem-like structure that bears leaf-like blades, each normally consisting of a single layer of undifferentiated cells except the midrib
  • Lac vascular tissues hence they do not have true roots, stems, or leaves
  • Some have water-conducting cells and sugar-conducting cells (not specialized or as effective as the ones of vascular plants)
  • Moss sporocyte is initially green and photosynthetic but turns golden brown at maturity
• BRYOPHYTA - (Mosses)

  Significance:

  • Important in forming soil
  • Prevents soil erosion
  • Retain moisture that they and other organisms need
  • Used by some bird species as nesting material along with twigs and grasses