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Bryophytes
Bryophytes are nonvascular plant; examples are mosses and their
relatives.
WHERE THEY ARE FOUND
THRIVE IN WET ENVIRONMENTS OR IN
AREAS WHERE THERE IS LOTS OF
RAINFALL AT LEAST PART OF THE YEAR
SWAMPS
MARSHES
NEAR STREAMS,
RAINFORESTS
ALONG THE WEST COAST OF BC & STATES
Unique to Bryophytes
have no lignin
usually
are small, low-
lying, (generally)
moisture-loving
plants
have no roots,
only filamentous
rhizoids
THE ONLY LAND PLANTS WITH A DOMINANT
GAMETOPHYTE! The sporophyte is parasitic on the
gametophyte. This stems from the embryo being retained
in the female sex organ of the gametophyte.
Groups of bryophytes
Bryophytes included mosses, liverworts, and
hornworts.
Mosses Liverworts Hornworts
SCARCER THAN MOSSES
NEED TO LIVE IN
PLACES THAT ARE
CONSTANTLY WET
LOOK LIKE FLAT
LEAVES GROWING
ALONG THE GROUND
LIVERWORTS
HORNWORT
LOOK LIKE GAMETOPHYTE OF LIVERWORT
SPOROPHYTE LOOKS LIKE
A HORN
Mosses
Most common bryophytes are mosses, which are members of the
phylum Bryophyta.
Mosses grow most abundantly in areas with water-in swamps and
bogs, near streams, and in rain forests.
BRYOPHYTES LACK SEVERAL
CRITICAL ADAPTATIONS TO
DRY PLACES
LACK WATER CONDUCTING TUBES
IN BRYOPHYTES, WATER PASSES FROM CELL TO CELL BY OSMOSIS & BY
MEANS OF SURFACE TENSION AROUND THE STEMS
WHAT DOES THIS MEAN?
WHAT ELSE?
BRYOPHYTES LACK PROTECTIVE SURFACE COVERING TO
KEEP WATER FROM EVAPORTAING FROM THEIR CELLS
WHAT DOES THIS MEAN?
THERE IS MORE
THEY LACK TRUE ROOTS
ROOTS CONTAIN WATER CONDUCTING TUBES THAT
ENABLE A PLANT TO ABSORB AND TRANSPORT WATER
EFFICIENTLY
THEY HAVE RHIZOIDS INSTEAD
WHAT IS THEIR FUNCTION?
Rhizoids
Rhizoid are in fungi, a root like hypha that
penetrates the surface of an object; in mosses, a
long, thin cell that anchors the moss to the ground
and absorbs water and minerals from the
surrounding soil.
Protonema
Protonema is the mass of tangled green filaments in
mosses that forms during germination.
Antheridia
Antheridum is the male reproductive structure in
some algae and plants.
Archegonia
Archegonium is the female reproductive structure in
some plants, including mosses and liverworts.
During at least one stage of their life cycle, bryophytes produce sperm that must swim through water to reach eggs of other individuals.
Therefore, they must live in places where there is rainfall or dew for at least part of the year
Role of Bryophytes
Many are pioneer plants, growing on bare rock and contributing to soil development.
In bogs and mountain forests they form a thick carpet, reducing erosion.
In forest ecosystems they act like a sponge retaining and slowly releasing water
They provide habitat for other plants and small animals as well as microorganisms like N2-fixing blue-green bacteria
Lacking a cuticle and transport tissue they readily absorb whatever is around them and can serve as bio-indicators of pollution and environmental degradation
