General Description 
        
          -             Anabaena cells are usually arranged in filaments or chains and can be straight, spiralled, coiled or spring-like and often dscribed as "beaded"          
 
          -             Filaments also have specialized cells called heterocysts and akinetes, used for fixing nitrogen and regenerating cells for future colonies          
 
          -             A mucilagenous sheath surrounds the cells of the filament          
 
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