CYNOBACTERIA
* It is also called as true bacteria
* they are characterized by the presence of rigid cell wall.
* they are of various types.
* CYNOBACTERIA- it is also called as blue-green algae. it has chlorophyll 'a' ,hence it is photosynthetic autotroph.
* the CNB may be unicellular, colonial, filamentous, marine or terrestrial.
* the colonies are generally surrounded by gelatinous sheath.
* some of these organism fix nitrogen in specialised cell called heterocysts e.g. Nostoc, Anabaena.
* CHEMOSYNTHETIC AUTOTROPHIC BACTERIA oxidise various inorganic substances such as nitrate,nitrite and ammoniaand use the released energy for their ATP production.
* chemosynthetic bacteria play a great role in recycle of nitrogen, phosphorus, sulphur, iron ect.
* HETEROTROPHIC BACTERIA are mostly found in nature.
* the majority are important decomposure.
* some bacteria are useful for human being like lactobacillus (convert milk into curd) and some are pathogenic cause disease.
* bacteria reproduce mainly by fission.
* in unfavourable condition bacteria produces spores.
* bacteria also reproduce by a sort of sexual reproduction by adopting a primitive DNA of another bacteria
* MYCOPLASMA are the smallest living known,which can survive without oxygen too. it has lack of cell wall.
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