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A Handbook of Biology
They lack true roots, stem or leaves. They may possess root-like, leaf-like
or stem-like structures.
The main plant body is haploid. It produces gametes, hence is called a
gametophyte.
The sex organs in bryophytes are multicellular.
The male sex organ (antheridium) produces biflagellate antherozoids.
The female sex organ (archegonium) is flask shaped and produces a
single egg.
Antherozoids are released into water where they come in contact with
archegonium. An antherozoid fuses with the egg to form zygote.
Zygotes do not undergo meiosis immediately. They produce a multicellular
body called a sporophyte.
ÏMPØRTÅÑÇË ØF BRÝØPHÝTËS
Some mosses provide food for herbivorous mammals, birds
and other animals.
Species of Sphagnum (a moss) provide peat. It is used as fuel.
It has water holding capacity so it is used as packing material
for trans-shipment of living material. (AIPMT 2006)
They have great ecological importance because of their
important role in plant succession on bare rocks/soil.
Mosses along with lichens decompose rocks making the
substrate suitable for the growth of higher plants. Since mosses
form dense mats on the soil, they can prevent soil erosion.
The bryophytes are divided into liverworts and mosses.
LÏVËRWØRTS
Grow in moist, shady habitats.
Plant body of a liverwort is thalloid. Eg. Marchantia
Leafy members have tiny leaf-like appendages in two rows on the stem-
like structures.