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flowers are complex and the seeds are enclosed in the fruit. They are divided into two classes :
(i) Monocotyledons—the group) with one colytedon in the embryo of the seed.
(ii) Dicotyledons—the group with two colytedons in the embryo of the seed.
Monocotyledons Are further divided into seven series, while Dicotyledons, being the larger group are divided into three sub-class-es each of which is further divided into various series. Each of the series is again divided into orders and the order into families and so on. In the flowering plants study of the family is considered most important.
Of the 342,000 species of plants on record, the following is the rough distribution :
Thailophyta Bryophyta Pteridophyta Gymnosperms Monocotyledons Dicotyledons
110,000 species 22,300 species 10,000 spec ies 700 species 40,000 species 159,000 species
From the above, it is seen that angiosperms constitute, 199,000 i.e. 60% of total species of plants.
FORM, STRUCTURE AND CLASSIFICATION OF ANIMALS
The animal kingdom is divided into ten major groups called phyla (sing.---phylum). One of these groups is of CHORDATES and the remaining ones are NON-CHORDATES.
The group CHORDATA is considered as a phylum and is divided into four sub-phyla, of which only in one group, the notochord (a stiff rod of cells below the tubular nerve and above the alimentary canal distinguishing Chordates and Non-chordates) gets replaced by the
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