Feb 9, 2011

Evolution of Plants

 Evolution is started since, when the first atom is created !!!
The first evolutionary organism for both plants and animals are bacteria.Some bacteria evoluted to form the huge plant kingdom and some other as a seed for animal kingdom.Such bacteria which decided to form the plant kingdom are evoluted to fungi and algae, which are the first multicellular organization among the plant kingdom.But even today it is in a debate that fungi or algae which originated first?
The plant body of fungi is called mycelium.It is made up of mass of thread like filaments called hyphae.Hyphae is made up of mass of cells whose cell wall is made up of chitin or fungal cellulose.
Algae are said to be unicellular plants which contains primitive chlorophyll pigments.They are the rich source of oxygen.Their habitat is aquatic.Their cell wall is similar to that of the higher plants.
Algae gave rise to a kingdom called bryophytes.These are considered as the amphibians of the plant kingdom, since this was the first step taken by algae to begin it’s terrestrial life.It is followed by pteridophytes,gymnosperms and at last higher plants called angiosperms.
Gymnosperms differs from angiosperms since it does not produces the fruit, but there is flower or may be inflorescence.pteridophytes are the first complete terrestrial organisms of the plant kingdom.They differs from their higher plants since they cannot able to produce the mature seed originated from ovule.Hence gymnosperms and angiosperms are together called as spermatophytes means seed producing plants.

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