Their morphological and functional harmony and improvements during evolution are just astonishing. The building blocks of life. Bacteria are cells without nuclei, therefore they are called Prokaryota . These bacteria have no membrane-bound nucleus. The genetic material inherited is dispersed through the cytoplasm.
Bacteria usually form large communities within their niche and replicate very rapidly.
A mature and rather old bacterium will rejuvenate in this manner. There is fibrillar material around the bacterium. Most bacteria and other cells simply produce their own typical extracellular matrix as an inseparable part of their environment. There are good reasons to believe that nuclei, mitochondria and possibly some other cell organelles like flagella have a symbiotic origin. Amoeba are unicellular living beings with nuclei, therefore they belong to Eukaryota like all other nucleus-bearing cells do.