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coccus




Gram positive cocci
Gram positive cocci
A bacterium with a rounded or spherical shape. Cocci may be true spheres (e.g., staphylococci), helmet-shaped (e.g., pneumococci), or kidney-shaped (e.g., Neisseriae). They may occur alone, in pairs, or in groups. If found in pairs they are called diplococci, threes are a triad, etc. Other group types include: tetracoccus (groups of four), streptococcus (chains), sarcina (cubes of eight), and staphylococcus (irregular clusters). Diseases caused by cocci include pneumonia, tonsillitis, bacterial heart disease, meningitis, sepsis, and various skin diseases.


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   • MICROBIOLOGY