Carolos Linnaeus divided the world of living organisms into two kingdoms: animal kingdom and plant kingdom . There are millions of species of plants. They vary from small size to a large size. On the basis of presence or absence of flowers, all the plants are divided into two major sub-kingdoms: cryptogams and phanerogams.
They are promitive and somplest plants without flowers. They are On the basis of appearance and stage of development, cryptogams are divided into three divisions. They are: Thallophyta, bryophyta and pteridophyta.
They are the most primitive and the simplest plants. They may be multicellular or multicellular. They possess following characteristics:
Thallophyta is divided into two sub-divisions. They are algae and fungi.
Algae are the green thallophytes which have the following characteristics:
Examples: spirogyra, sea-weeds, volvox, etc.
Fungi include non-green plants and have following characteristics:
Examples: mushroom, mucor, yeast, ring worm etc.
Bryophyta have the following characteristics:
Examples: moss, liverworts etc.
Pteridophyta are seedless vascular plants . They are seedless vascular plants and have the following characteristics:
Examples: fern, horsetail, paniamala etc.
The major groups of plant kingdom are:
i) Cryptogams (Non-flowering) and
ii) Phanerogams (flowering)
The groups of plants which do not bear flower and seeds are called cryptogams. It is sub-divided into three divisions:
The characteristics feature of cryptogams are:
i) They do not bear flower and seed.
ii) They are lower plants.
iii) They reproduce by both a sexual and asexual methods.
iv) They may be unicellular or multicellular.
v) Their mode of nutrition is autotrophic or heterotrophic.
Some features of Thallophyta are as follows:
i) The plant body is not differentiated into roots, stems and leaves.
ii) They may be unicellular or multicellular.
iii) They are autotrophic or heterotrophic.
The differences between algae and fungi are as follows:
|i) Algae are autotrophic.||i) Fungi are heterotrophic.|
|ii) The cell wall is made up of cellulose.||ii) The cell wall or hyphae wall is of fungal cellulose or chitin.|
|iii) They reproduce both by sexually and asexually.||iii) Reproduction is by formation of spores and sexual method.|
The plants which prepare their own food are known as autotroph.
The plant which does not prepare their own food is known as heterotroph.
Sub-division = Algae
i) It prepares food itself due to presence of chlorophyll.
ii) It is mostly aquatic, only few species are terrestrial.
Sub-division = fungi
i) Fungi are heterotrophic.
ii) They obtain their nutrition as saprophytes or parasites.
A thin film of water is necessary for fertilization in bryophyte. The moisture should be available for a least part of year so that motile antherzoids may swim to the archegonium through a film of water. So, water is necessary for the completion life cycle through the plants grow on land. Thus, the bryophytes are called amphibians of plant kingdom.
The three features of bryophyte are as follows:
i) They show alternation of generation with gametophyte as main generation.
ii) They are found in moist and shady places.
iii) They prepare their own food due to the presence of chlorophyll.
The important features of pteridophyta are as follows:
i) They are sporophyte.
ii) They possess xylem and phloem tissues.
e.g. fern, horse tail, lycopodium, selaginnellia, equisetum etc.
Pteridophytes are more advanced than Bryophytes due to the following reasons:
a) Plant body is well developed into root, stem and leaves.
b) Pteridophytes possess vascular tissues: xylem and phloem.
Division of the following organisms are as follows:
Horse tail Pteridophyta
The difference between moss and fern are as follows:
|It falls on bryophyta division.||It falls on pteridophyta division.|
|It does not contain xylem and phloem tissues.||It contains xylem and phloem tissues.|
Fern plants are important because
i) They can be used in decorative purposes.
ii) They are used as medicinal herbs.
Thallophyta is divided into two sub-divisions. They are ______.
bryophyta and pteridophyta.
Thallophyta and bryophyta
algae and fungi
algae and fern
Cryptogams as a group differ from bryophytes in the ______.
presence of vascular tissue
none of these
Heterospory is production of ______.
all of the above
large and small spores
sexual and asexual spore
haploid and diploid spore
Fern stele is a ______.
none of these