Bacteria - referred to as cocci (the singular is coccus);...

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Bacteria Members of the kingdom Monera are microscopic organisms that include the bacteria and  cyanobacteria. Both the bacteria and cyanobacteria are prokaryotes.  Prokaryotes  lack a nucleus,  and they have no organelles except ribosomes. The hereditary material exists as a single loop of  double-stranded DNA in a nuclear region, or nucleoid. Members of the kingdom multiply by an  asexual process called  binary fission . No evidence of mitosis is apparent in the reproductive process.  Bacteria live in virtually all the environments on earth, including the soil, water, and air. They have  existed for approximately 3 billion years, and they have evolved into every conceivable ecological  niche on, above, and below the surface of the earth. Most bacteria can be divided into three groups according to their shapes. The spherical bacteria are 
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Unformatted text preview: referred to as cocci (the singular is coccus); the rod-shaped bacteria are bacilli (the singular is bacillus ); and the spiral bacteria are spirochetes if they are rigid or spirilla (the singular is spirillum ) if they are flexible. Cocci may occur in different forms. Those cocci that appear as an irregular cluster are staphylococci (the singular is staphylococcus ) and are the cause of staph infections. Cocci in beadlike chains are streptococci , and bacteria in pairs are diplococci . One streptococcus is the cause of strep throat, while another is a harmless organism used to make yogurt. A species of diplococcus is the agent of pneumonia, while a second causes gonorrhea, and a third is the agent of meningitis....
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